WO2019107105A1 - Wireless communication apparatus - Google Patents

Wireless communication apparatus Download PDF

Info

Publication number
WO2019107105A1
WO2019107105A1 PCT/JP2018/041483 JP2018041483W WO2019107105A1 WO 2019107105 A1 WO2019107105 A1 WO 2019107105A1 JP 2018041483 W JP2018041483 W JP 2018041483W WO 2019107105 A1 WO2019107105 A1 WO 2019107105A1
Authority
WO
WIPO (PCT)
Prior art keywords
signal
frequency
noise
filter
local
Prior art date
Application number
PCT/JP2018/041483
Other languages
French (fr)
Japanese (ja)
Inventor
伊藤　健一
雅司 大室
祐 石渡
Original Assignee
株式会社村田製作所
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社村田製作所 filed Critical 株式会社村田製作所
Priority to JP2019557107A priority Critical patent/JP6737409B2/en
Priority to KR1020207015056A priority patent/KR102348617B1/en
Priority to CN201880077421.0A priority patent/CN111492588B/en
Publication of WO2019107105A1 publication Critical patent/WO2019107105A1/en
Priority to US16/886,422 priority patent/US11050448B2/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/18—Input circuits, e.g. for coupling to an antenna or a transmission line
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/01—Frequency selective two-port networks
    • H03H7/0115—Frequency selective two-port networks comprising only inductors and capacitors
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40—Circuits

Definitions

  • the present invention relates to a wireless communication apparatus suitable for use in high frequency signals such as microwaves and millimeter waves, for example.
  • a receiver including an antenna, a mixer, a multiplier, and a local oscillator is known as a wireless communication apparatus used for high frequency signals (see, for example, Patent Document 1).
  • the local signal output from the local oscillator is frequency-multiplied by the multiplier and input to the mixer, and the high frequency signal received by the antenna is input to the mixer.
  • the mixer mixes the signal from the multiplier and the high frequency signal, and outputs a signal obtained by down converting and up converting the high frequency signal.
  • the multiplier multiplies the frequency of the local signal generated by the local oscillator.
  • noise signals may be mixed in from the signal path between the multiplier and the local oscillator.
  • the multiplier frequency-multiplies the local signal mixed with the noise signal intermodulation occurs in the multiplier, and an unnecessary noise spectrum is generated as high-order intermodulation distortion.
  • a signal including the unnecessary noise spectrum is input to the mixer and signal-combined with the high frequency signal received by the antenna, the original communication signal band and the noise band may overlap.
  • this combined signal is input to the demodulation circuit on the receiving side, it is judged as erroneous data, and there is a problem that data communication can not be performed.
  • the present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a wireless communication apparatus that suppresses the intermodulation distortion of a frequency multiplier to prevent the generation of noise.
  • the present invention provides an antenna for transmitting or receiving a high frequency signal having a predetermined bandwidth, a local oscillator for outputting a local signal having a lower center frequency than the high frequency signal, and the local
  • a radio communication apparatus comprising: a frequency multiplier that frequency-multiplies a signal, and a frequency multiplier electrically connected to the local oscillator; and a mixer connected to the antenna and the frequency multiplier.
  • a filter for passing the local signal and removing a noise signal of a frequency different from that of the local signal is provided between the frequency multiplier and the filter, and the filter is a center frequency of the local signal and a center of the noise signal. Removing the noise signal satisfying the relation that the absolute value of the frequency difference with the frequency is smaller than the bandwidth of the high frequency signal It is characterized by a door.
  • a filter is provided between the local oscillator and the frequency multiplier for removing noise signals of a frequency different from that of the local signal. Therefore, since the frequency multiplier frequency-multiplies only the local signal from which the noise signal has been removed, the intermodulation distortion of the frequency multiplier can be suppressed to prevent the generation of noise.
  • the frequency multiplier frequency-multiplies the local signal mixed with the noise signal, an unnecessary noise spectrum is generated.
  • the mixer when the absolute value of the frequency difference between the center frequency of the local signal and the center frequency of the noise signal is smaller than the bandwidth of the high frequency signal, the mixer generates noise based on the unnecessary noise spectrum output from the frequency multiplier. Noise is also generated at the output of the high frequency signal, and the band of the high frequency signal and the noise band overlap. This point is not limited to the mixer that performs down conversion on the reception side, and the same applies to a mixer that performs up conversion on the transmission side.
  • the filter removes the noise signal that satisfies the relationship that the absolute value of the frequency difference between the center frequency of the local signal and the center frequency of the noise signal is smaller than the bandwidth of the high frequency signal. Therefore, overlapping of the communication signal band and the noise band can be prevented.
  • FIG. 1 is a block diagram showing a receiver according to a first embodiment of the present invention. It is a circuit diagram which shows the filter in FIG.
  • FIG. 5 is a characteristic diagram showing frequency characteristics of insertion loss of the filter in FIG. 2; It is a block diagram which shows the receiver by a comparative example. It is a circuit diagram showing the filter by the 1st modification. It is a circuit diagram showing the filter by the 2nd modification. It is a circuit diagram showing the filter by the 3rd modification. It is a block diagram showing the transmitting and receiving device by a 2nd embodiment of the present invention.
  • FIG. 1 shows a receiving apparatus 1 as a wireless communication apparatus according to a first embodiment of the present invention.
  • the receiver 1 includes an antenna 2, a local oscillator 3, a frequency multiplier 4, a mixer 5, a demodulation circuit 7, a filter 8 and the like.
  • the antenna 2 receives a high frequency signal SH of a predetermined bandwidth X.
  • the antenna 2 is connected to the mixer 5.
  • the center frequency FH of the high frequency signal SH is set to, for example, 3 GHz.
  • the bandwidth X is set to, for example, 300 MHz.
  • the antenna 2 inputs the high frequency signal SH to the mixer 5.
  • the antenna 2 does not have to be directly connected to the mixer 5, and may be connected indirectly via, for example, a low noise amplifier or a band pass filter.
  • the local oscillator 3 outputs a local signal SL having a center frequency FL lower than that of the high frequency signal SH.
  • the center frequency FL of the local signal SL is set to, for example, 500 MHz.
  • the local oscillator 3 is electrically connected to the frequency multiplier 4.
  • the frequency multiplier 4 outputs a signal Sm obtained by frequency-multiplying the local signal SL. Specifically, the frequency multiplier 4 outputs a signal Sm that is an integral multiple (for example, twice) of the center frequency FL. Thus, the center frequency Fm of the signal Sm is, for example, 1 GHz.
  • the output side of the frequency multiplier 4 is connected to the mixer 5.
  • the frequency multiplier 4 is not limited to double the center frequency FL of the local signal SL, but may be, for example, triple or quadruple or more.
  • the mixer 5 is connected to the antenna 2 and the frequency multiplier 4.
  • the mixer 5 combines the signal Sm output from the frequency multiplier 4 and the high frequency signal SH output from the antenna 2 and outputs a combined signal Sc.
  • the combined signal Sc includes a down-converted signal Sd obtained by down-converting the high-frequency signal SH and an up-converted signal Su obtained by up-converting the high-frequency signal SH.
  • the center frequency Fd of the down-converted signal Sd is, for example, 2 GHz as a value obtained by subtracting the difference between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm from the center frequency FH of the high frequency signal SH.
  • the center frequency Fu of the up-conversion signal Su is, for example, 4 GHz as a value obtained by adding the difference between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm from the center frequency FH of the high frequency signal SH.
  • the output side of the mixer 5 is connected to the demodulation circuit 7 via the band pass filter 6.
  • the band pass filter 6 removes the unnecessary up-converted signal Su from the combined signal Sc, and outputs the down-converted signal Sd to the demodulation circuit 7.
  • the mixer 5 for reception combines the high frequency signal SH and the signal Sm obtained by frequency-multiplying the local signal SL, and outputs a low frequency signal (down converted signal Sd) obtained by down converting the high frequency signal SH. It functions as a mixer.
  • the demodulation circuit 7 includes, for example, a detection circuit, an AD converter, and the like, demodulates the signal using the down-converted signal Sd, and generates a baseband signal for reception.
  • the filter 8 is provided between the local oscillator 3 and the frequency multiplier 4.
  • the filter 8 removes the noise signal N having a frequency different from that of the local signal SL.
  • ) is removed.
  • the noise signal N is, for example, another high frequency signal SHn used for wireless communication of a frequency band different from that of the high frequency signal SH.
  • the noise signal N is, for example, a 700 MHz band signal which is a low band of LTE (Long Term Evolution).
  • the filter 8 is configured by a band removal filter (BSF: Band Stop Filter) which passes the local signal SL and removes the noise signal N.
  • BSF Band Stop Filter
  • the filter 8 is configured by combining an inductor element Lp and a capacitor element Cp.
  • the BSF of the filter 8 is configured by a parallel resonant circuit 8A in which an inductor element Lp and a capacitor element Cp are connected in parallel.
  • the parallel resonance frequency of the filter 8 is set to, for example, 700 MHz as the center frequency Fn of the noise signal N (see FIG. 3).
  • the receiver 1 according to the present embodiment has the above-described configuration, and its operation will be described next.
  • the local oscillator 3 generates a sine wave signal of 500 MHz single frequency (center frequency FL) as the local signal SL.
  • the local signal SL is converted by the frequency multiplier 4 into a signal Sm which has an integral multiple (for example, double) frequency (center frequency Fm).
  • the center frequency Fm of the signal Sm is 1 GHz.
  • the high frequency signal SH received by the antenna 2 and the frequency-converted signal Sm are input to the mixer 5.
  • the mixer 5 combines the high frequency signal SH and the signal Sm obtained by frequency-multiplying the local signal SL, and outputs a combined signal Sc.
  • the combined signal Sc includes the down-converted signal Sd and the up-converted signal Su.
  • the center frequency Fd of the down converted signal Sd is a value (FH ⁇ Fm) obtained by subtracting the center frequency Fm of the signal Sm from the center frequency FH of the high frequency signal SH, and is 2 GHz.
  • the center frequency Fu of the up-conversion signal Su is a value (FH + Fm) obtained by adding the center frequency Fm of the signal Sm to the center frequency FH of the high frequency signal SH, which is 4 GHz.
  • the down-converted signal Sd and the up-converted signal Su both have the same bandwidth X as the high frequency signal SH.
  • the band pass filter 6 selects a down converted signal Sd which is a signal necessary for communication from the down converted signal Sd of the combined signal Sc and the up converted signal Su.
  • the band pass filter 6 outputs the down converted signal Sd to the demodulation circuit 7.
  • the antenna 10 of the wireless communication system different from the wireless communication system used by the antenna 2 may be arrange
  • the antenna 10 performs wireless communication independently of the antenna 2 and emits radio waves. Therefore, the reception of the high frequency signal SH by the antenna 2 and the emission of the radio wave (the high frequency signal SHn) from the antenna 10 may be performed simultaneously. This state is likely to occur, for example, in a small wireless terminal such as a smartphone.
  • each antenna emits high-output radio waves of several dB to about 30 dB in order to secure a communication distance.
  • the antenna 10 of one wireless communication scheme is disposed in proximity to the wireless communication device of the other wireless communication scheme.
  • the respective antennas 2 and 10 emit radio waves of high power. Therefore, the radio wave of the antenna 10 is coupled to the high frequency component of the radio communication device, and the radio wave of the antenna 10 is a noise signal on the signal line of the local signal SL, ie, the signal line between the local oscillator 3 and the frequency multiplier 4 It may invade as N.
  • the center frequency of the LTE low band is 700 MHz, which is close to 500 MHz which is the center frequency FL of the local signal SL.
  • the high frequency signal SHn (a signal of 700 MHz) emitted from the antenna 10 is conducted as a noise signal N to the signal line of the local signal SL.
  • the center frequency Fn of the noise signal N is higher than the center frequency FL of the local signal SL (Fn> FL) will be described.
  • the problems described below also occur when the center frequency Fn of the noise signal N is lower than the center frequency FL of the local signal SL (Fn ⁇ FL).
  • FIG. 4 shows a configuration in which the filter 8 of the present invention is omitted as the receiving device 11 according to the comparative example.
  • a signal SLn in which the noise signal N propagated from the antenna 10 is mixed into the original local signal SL is input to the frequency multiplier 4.
  • the frequency multiplier 4 in order for the frequency multiplier 4 to operate normally, a single frequency signal needs to be input.
  • the signal SLn including the noise signal N in the original local signal SL is input to the frequency multiplier 4
  • the signal SLn having two frequencies instead of a single frequency is input. It will be.
  • FIG. 4 shows an example of second-order intermodulation distortion among higher-order intermodulation distortion. That is, the signal Smn after passing through the frequency multiplier 4 includes the signal Sm obtained by frequency-multiplying the original local signal SL and the unnecessary noise spectrum (N1 and N2) generated by the intermodulation.
  • the frequency of the noise N1 included in the signal Smn is a value obtained by subtracting the difference (Fn ⁇ FL) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL from the center frequency Fm of the signal Sm ⁇ Fm ⁇ (Fn -FL) ⁇ , for example 800 MHz.
  • the frequency of the noise N2 included in the signal Smn is a value ⁇ Fm + (sum of difference (Fn ⁇ FL) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL from the center frequency Fm of the signal Sm).
  • Fn-FL 1.2 GHz.
  • noises N3 to N6 are generated in addition to the down-converted signal Sd and the up-converted signal Su which are the original communication signals.
  • Noises N3 and N4 occur in the peripheral band of the down-converted signal Sd.
  • Noises N5 and N6 occur in the peripheral band of the up-converted signal Su.
  • the center frequency of the noise N3 is the difference between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm obtained by frequency multiplication of the original local signal SL (FH ⁇ Fm) to the center frequency Fn of the noise signal N And the value (FH ⁇ Fm) ⁇ (Fn ⁇ FL) ⁇ obtained by subtracting the difference (Fn ⁇ FL) between the local signal SL and the center frequency FL of the local signal SL, for example, 1.8 GHz.
  • the noise N3 has the same bandwidth X as the high frequency signal SH.
  • the center frequency of the noise N4 is the difference (FH ⁇ Fm) between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm, and the difference between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL
  • the sum of Fn ⁇ FL) is ⁇ (FH ⁇ Fm) + (Fn ⁇ FL) ⁇ , for example, 2.2 GHz.
  • the noise N4 has the same bandwidth X as the high frequency signal SH.
  • the center frequency of the noise N5 is the sum (FH + Fm) of the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm to the difference (Fn) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL.
  • the value obtained by subtracting ⁇ FL) is ⁇ (FH + Fm) ⁇ (Fn ⁇ FL) ⁇ , for example, 3.8 GHz.
  • the noise N5 has the same bandwidth X as the high frequency signal SH.
  • the center frequency of the noise N6 is the sum (FH + Fm) of the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm, and the difference (Fn ⁇ ) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL. It becomes the value ⁇ (FH + Fm) + (Fn-FL) ⁇ which added FL) and becomes 4.2 GHz, for example.
  • the noise N6 has, for example, the same bandwidth X as the high frequency signal SH.
  • the original communication signal is The noise band overlaps the band. That is, when the bandwidth X is larger than the absolute value of the frequency difference ⁇ F between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL (X>
  • the composite signal Smn in which the noise band overlaps the band of the original communication signal is transmitted to an IC (integrated circuit) such as the demodulation circuit 7 on the reception side.
  • an IC integrated circuit
  • data is demodulated based on the combined signal Smn in the IC on the receiving side.
  • the band pass filter 6 provided between the mixer 5 and the demodulation circuit 7 removes the up-converted signal Su and the noises N5 and N6 from the combined signal Smn. Therefore, in addition to the down-converted signal Sd, noises N3 and N4 are inputted to the IC on the receiving side.
  • the IC on the receiving side recognizes the content of the high frequency signal SH as a data arrangement or data pattern which is different due to the noises N3 and N4. That is, even when the down-converted signal Sd based on the high frequency signal SH is input, the IC on the receiving side recognizes the content of the high frequency signal SH as erroneous data by the noises N3 and N4. As described above, when a normal communication signal can not be received, the IC on the receiving side requests the transmitting side to retransmit data. Repeated occurrence of this re-transmission reduces the communication speed at the antenna 2, and in the worst case, the communication becomes impossible.
  • the filter 9 for removing the noise signal N other than the local signal SL is provided between the local oscillator 3 and the frequency multiplier 4. Therefore, even if the radio wave (high frequency signal of 700 MHz band) of the antenna 10 intrudes into the signal line connecting the local oscillator 3 and the frequency multiplier 4, the filter 9 suppresses the noise signal N in the radio frequency band. be able to. As a result, the noise signal N is not input to the frequency multiplier 4.
  • a band elimination filter that can suppress noise in the radio frequency band (for example, 700 MHz band) of the antenna 10.
  • the filter 8 since the original local signal SL is a signal necessary for communication, the filter 8 needs to eliminate the influence on the local signal SL. Therefore, the filter 8 needs to have the function of a band pass filter in the frequency band of the original local signal SL.
  • FIG. 2 shows the configuration of the filter 8 according to the present embodiment.
  • the filter 8 according to the present embodiment is constituted by an LC filter in which an inductor element Lp and a capacitor element Cp are connected in parallel.
  • the inductance of the inductor element Lp is, for example, 6 nH
  • the capacitance of the capacitor element Cp is 8 pF.
  • these specific numerical values are appropriately set according to the original center frequency FL of the local signal SL and the center frequency Fn of the noise signal N.
  • the inductance of the inductor element Lp and the capacitance of the capacitor element Cp are appropriately selected so that the loss is low at the center frequency FL of the local signal SL and is high loss at the center frequency Fn of the noise signal N.
  • FIG. 3 shows the frequency characteristic of the insertion loss by the filter 8 in FIG.
  • the insertion loss of the filter 8 (LC filter) according to the present embodiment is 0.5 dB at 500 MHz which is the center frequency FL of the original local signal SL, and at the center frequency Fn of the noise signal N. It is 11 dB at a certain 700 MHz.
  • a communication test was performed by inserting the filter 8 shown in FIG. 2 into a signal line connecting the local oscillator 3 and the frequency multiplier 4. As a result, while radio communication at the antenna 2 was impossible before the insertion of the filter 8, communication became possible after the insertion of the filter 8 according to the present embodiment. It was also confirmed that the communication speed was also the original data transfer speed.
  • a filter 8 is provided between the local oscillator 3 and the frequency multiplier 4 for removing the noise signal N having a frequency different from that of the local signal SL.
  • the frequency multiplier 4 frequency-multiplies the local signal SL from which the noise signal N has been removed, so intermodulation distortion of the frequency multiplier 4 can be suppressed and generation of noise can be prevented.
  • the frequency multiplier 4 frequency-multiplies the local signal SL mixed with the noise signal N, an unnecessary noise spectrum is generated.
  • noise is also generated in the output from the mixer 5 based on the unnecessary noise spectrum output from the frequency multiplier 4, and the band of the high frequency signal SH and the noise band overlap.
  • the filter 8 satisfies the noise signal N satisfying the relationship that the absolute value of the frequency difference .DELTA.F between the center frequency FL of the local signal SL and the center frequency Fn of the noise signal N is smaller than the bandwidth X of the high frequency signal SH. Remove. For this reason, the noise output from the mixer 5 can be suppressed, and overlapping of the communication signal band and the noise band can be prevented.
  • the noise signal whose absolute value of the frequency difference ⁇ F is larger than the bandwidth X of the high frequency signal SH need not necessarily be removed. Even if the mixer generates noise based on such noise signals, the communication signal band and the noise band do not overlap, and the frequency bands of the communication signal (for example, the down-converted signal Sd) and the noise are mutually separated. . Therefore, the noise generated by the mixer 5 can be removed by, for example, a band pass filter or the like.
  • the filter 8 can be configured by a band elimination filter.
  • the band elimination filter is configured to have a low loss at the center frequency FL of the local signal SL and a high loss at the center frequency Fn of the noise signal N.
  • the filter 8 including the band elimination filter can pass the local signal SL and can remove the noise signal N.
  • the filter 8 since the filter 8 is configured by combining the inductor element Lp and the capacitor element Cp, the filter 8 can be easily configured using a passive element.
  • the band elimination filter of the filter 8 is configured to include the parallel resonant circuit 8A of the inductor element Lp and the capacitor element Cp. Therefore, by setting the resonance frequency of the parallel resonance circuit 8A to the center frequency Fn of the noise signal N, the signal attenuation can be increased in the band of the center frequency Fn, and the signal attenuation is reduced in the other bands. be able to. Therefore, even when the center frequency FL of the local signal SL and the center frequency Fn of the noise signal N are close to each other, the filter 8 can pass the local signal SL to remove the noise signal N.
  • the noise signal N is another high frequency signal SHn used for wireless communication of a frequency band different from the high frequency signal SH, even when the other high frequency signal SHn has a center frequency close to the local signal SL Noise due to the high frequency signal SHn can be suppressed.
  • the filter 8 is constituted by a band elimination filter composed of one stage of parallel resonance circuit 8A.
  • the present invention is not limited to this, and may be configured by a band elimination filter including two stages of parallel resonant circuits 21A and 21B, for example, as a filter 21 according to a first modification shown in FIG.
  • a series circuit 21C in which an inductor element La and a capacitor element Ca are connected in series is connected between the connection point of the two parallel resonant circuits 21A and 21B and the ground.
  • the filter may be constituted by a band elimination filter consisting of three or more stages of parallel resonant circuits.
  • the filter 22 is constituted by a band pass filter (BPF: Band Pass Filter) comprising a series resonant circuit 22A in which an inductor element Ls and a capacitor element Cs are connected in series. It is also good.
  • BPF Band Pass Filter
  • the inductance of the inductor element Ls and the capacitance of the capacitor element Cs are set such that the resonance frequency of the series resonant circuit 22A matches the center frequency FL of the local signal SL.
  • the filter 23 may be configured by a band pass filter composed of two-stage series resonant circuits 23A and 23B.
  • a parallel circuit 23C in which the inductor element Lb and the capacitor element Cb are connected in parallel is connected between the connection point of the two series resonant circuits 23A and 23B and the ground.
  • the filter may be constituted by a band pass filter consisting of three or more stages of series resonant circuits.
  • FIG. 8 shows a second embodiment of the present invention.
  • the feature of the second embodiment is that it is applied to a transmitting / receiving apparatus which performs both transmission and reception of high frequency signals as a wireless communication apparatus.
  • the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof will be omitted.
  • the transmitting and receiving apparatus 31 includes an antenna 2, a local oscillator 3, a frequency multiplier 4, a mixer 5 for reception, a demodulation circuit 7, and a filter 8 as in the first embodiment.
  • the transmission and reception apparatus 31 includes a modulation circuit 32 and a mixer 33 for transmission.
  • the receiving side portion of the transmission / reception device 31 is configured substantially the same as the reception device 1 according to the first embodiment. Therefore, the high frequency signal SHr received by the antenna 2 is combined with the signal Sm obtained by frequency-multiplying the local signal SL by the reception mixer 5. Thereby, the mixer 5 outputs the synthesized signal Scr including the up-converted signal and the down-converted signal. The up-conversion signal of the synthesized signal Scr is removed by the band pass filter 6. Therefore, the demodulation circuit 7 demodulates the signal based on the low frequency signal (down converted signal) obtained by down converting the high frequency signal SHr.
  • the transmission side portion of the transmission and reception apparatus 31 is configured by a modulation circuit 32, a mixer 33 for transmission, and the like.
  • the modulation circuit 32 includes, for example, a DA converter, and generates an intermediate frequency signal Si (low frequency signal) based on data for transmission.
  • the center frequency of the intermediate frequency signal Si is set to 2 GHz, for example.
  • the intermediate frequency signal Si has a predetermined bandwidth X (for example, 300 MHz).
  • the mixer 33 is connected to the antenna 2 and the frequency multiplier 4. In addition to this, the mixer 33 is connected to the modulation circuit 32.
  • the transmission mixer 33 is configured substantially the same as the reception mixer 5.
  • the mixer 33 combines the signal Sm output from the frequency multiplier 4 with the intermediate frequency signal Si output from the modulation circuit 32, and outputs a combined signal Sct.
  • the combined signal Sct includes a down-converted signal obtained by down-converting the intermediate frequency signal Si and an up-converted signal obtained by up-converting the intermediate frequency signal Si.
  • the center frequency of the down-converted signal is, for example, 1 GHz as a value obtained by subtracting the difference between the center frequency of the intermediate frequency signal Si and the center frequency Fm of the signal Sm from the center frequency of the intermediate frequency signal Si.
  • the center frequency of the up-conversion signal is, for example, 3 GHz as a value obtained by adding the difference between the center frequency of the intermediate frequency signal Si and the center frequency Fm of the signal Sm from the center frequency of the intermediate frequency signal Si.
  • Both the downconverted signal and the upconverted signal have a bandwidth X.
  • the mixer 33 is connected to the antenna 2 via the band pass filter 34.
  • the band pass filter 34 removes unnecessary down-converted signals from the combined signal Sct, and outputs the up-converted signal to the antenna 2. Therefore, the transmission mixer 33 combines the intermediate frequency signal Si (low frequency signal) and the signal Sm obtained by frequency-multiplying the local signal SL, and outputs a high frequency signal SHt obtained by up-converting the intermediate frequency signal Si. It functions as a conversion mixer.
  • the antenna 2 transmits a high frequency signal SHt.
  • the filter 8 removes the noise signal N satisfying the relation that the absolute value of the frequency difference ⁇ F between the center frequency FL of the local signal SL and the center frequency Fn of the noise signal N is smaller than the bandwidth X of the high frequency signal SHt. Do.
  • a power amplifier may be provided between the antenna 2 and the band pass filter 34 to amplify the power of the high frequency signal SHt.
  • an antenna duplexer, a circulator, or the like may be provided between the antenna 2 and the mixers 5 and 33 in order to separate signals for transmission and reception.
  • a filter 8 is provided between the local oscillator 3 and the frequency multiplier 4 to remove noise signals N other than the local signal SL. Therefore, the intermodulation distortion of the frequency multiplier 4 can be suppressed. As a result, since the signal from which the noise spectrum is reduced from the frequency multiplier 4 is input to the mixer 33, the noise output from the mixer 33 can be suppressed, and the overlapping of the communication signal band and the noise band can be prevented. be able to.
  • the receiving device 1 is illustrated as a wireless communication device
  • the transmitting and receiving device 31 is illustrated as a wireless communication device.
  • the present invention is not limited to this, and the wireless communication apparatus may be a transmitting apparatus having only a transmitting function.
  • the wireless communication apparatus used for millimeter waves has been described as an example, but the present invention may be applied to a wireless communication apparatus used for high frequency signals of other frequency bands such as microwaves.
  • the present invention comprises an antenna for transmitting or receiving a high frequency signal having a predetermined bandwidth, a local oscillator for outputting a local signal having a lower center frequency than the high frequency signal, and frequency-multiplying the local signal, the local oscillator
  • a wireless communication device comprising: a frequency multiplier electrically connected to each other; and a mixer connected to the antenna and the frequency multiplier, the wireless communication device comprising: And a filter for passing the local signal and removing a noise signal having a frequency different from that of the local signal, wherein the filter has an absolute value of a frequency difference between a center frequency of the local signal and a center frequency of the noise signal. It is characterized in that the noise signal satisfying the relation smaller than the bandwidth of the high frequency signal is removed. Thereby, the intermodulation distortion of the frequency multiplier can be suppressed, and the generation of noise can be prevented.
  • the filter is configured by a band pass filter or a band removal filter that passes the local signal and removes the noise signal.
  • the band pass filter allows the local signal to pass and removes noise signals of a frequency different from the local signal.
  • the band elimination filter can pass the local signal and remove the noise signal.
  • the filter is configured by combining an inductor element and a capacitor element. Therefore, the filter can be easily configured using passive elements.
  • the band pass filter includes a series resonance circuit of an inductor element and a capacitor element. Therefore, by setting the resonant frequency of the series resonant circuit to the center frequency of the local signal, the band pass filter can pass the local signal and remove the noise signal.
  • the band elimination filter is configured to include a parallel resonance circuit of an inductor element and a capacitor element. Therefore, by setting the resonant frequency of the parallel resonant circuit to the center frequency of the noise signal, the band elimination filter can pass the local signal and remove the noise signal.
  • the noise signal is another high frequency signal used for wireless communication of a frequency band different from that of the high frequency signal. Therefore, even when another high frequency signal has a center frequency close to that of the local signal, noise due to the other high frequency signal can be suppressed.
  • Reference Signs List 2 antenna 3 local oscillator 4 frequency multiplier 5, 33 mixers 8, 21, 22, 23 filters 8A, 21A, 21B parallel resonant circuits 22A, 23A, 23B series resonant circuits 31 transmitting / receiving apparatus (wireless communication apparatus)

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Noise Elimination (AREA)
  • Transceivers (AREA)

Abstract

According to the present invention, a reception device (1) is provided with: an antenna (2) for receiving a high-frequency signal (SH) having a bandwidth (X); and a mixer (5) connected to the antenna (2) and a frequency multiplier (4). A filter (8) for removing a noise signal (N) having a frequency different from that of a local signal (SL) is provided between a local oscillator (3) and the frequency multiplier (4). The filter (8) removes the noise signal (N) satisfying a relationship in which the absolute value of the frequency difference (ΔF) between the center frequency (FL) of the local signal (SL) and the center frequency (Fn) of the noise signal (N) is smaller than the bandwidth (X) of the high-frequency signal (SH).

Description

無線通信装置Wireless communication device
　本発明は、例えばマイクロ波やミリ波等の高周波信号に用いて好適な無線通信装置に関する。 The present invention relates to a wireless communication apparatus suitable for use in high frequency signals such as microwaves and millimeter waves, for example.
　高周波信号に用いる無線通信装置として、アンテナ、ミキサ、逓倍器、ローカル発振器を備えた受信装置が知られている（例えば、特許文献１参照）。特許文献１に記載された受信装置では、ローカル発振器から出力されたローカル信号を逓倍器によって周波数逓倍してミキサに入力すると共に、アンテナによって受信した高周波信号をミキサに入力する。このとき、ミキサは、逓倍器からの信号と高周波信号とを混合して、高周波信号をダウンコンバートおよびアップコンバートした信号を出力する。 A receiver including an antenna, a mixer, a multiplier, and a local oscillator is known as a wireless communication apparatus used for high frequency signals (see, for example, Patent Document 1). In the receiver described in Patent Document 1, the local signal output from the local oscillator is frequency-multiplied by the multiplier and input to the mixer, and the high frequency signal received by the antenna is input to the mixer. At this time, the mixer mixes the signal from the multiplier and the high frequency signal, and outputs a signal obtained by down converting and up converting the high frequency signal.
特開２０１４－１９５１６８号公報JP, 2014-195168, A
　ところで、特許文献１に記載された受信装置では、逓倍器は、ローカル発振器によるローカル信号を周波数逓倍している。一方、例えば、逓倍器とローカル発振器との間の信号経路からノイズ信号が混入することがある。この場合、ノイズ信号が混入したローカル信号を逓倍器が周波数逓倍すると、逓倍器で相互変調が起こり、高次の相互変調歪として不要なノイズスペクトラムが生成される。この不要なノイズスペクトラムを含んだ信号がミキサに入力され、アンテナで受信した高周波信号と信号合成されると、本来の通信信号帯域とノイズ帯域が重なることがある。この合成された信号が受信側の復調回路に入力されると、誤ったデータと判断され、データ通信ができなくなるという問題がある。 By the way, in the receiving device described in Patent Document 1, the multiplier multiplies the frequency of the local signal generated by the local oscillator. On the other hand, for example, noise signals may be mixed in from the signal path between the multiplier and the local oscillator. In this case, when the multiplier frequency-multiplies the local signal mixed with the noise signal, intermodulation occurs in the multiplier, and an unnecessary noise spectrum is generated as high-order intermodulation distortion. When a signal including the unnecessary noise spectrum is input to the mixer and signal-combined with the high frequency signal received by the antenna, the original communication signal band and the noise band may overlap. When this combined signal is input to the demodulation circuit on the receiving side, it is judged as erroneous data, and there is a problem that data communication can not be performed.
　本発明は上述した従来技術の問題に鑑みなされたもので、本発明の目的は、周波数逓倍器の相互変調歪みを抑制して、ノイズの発生を防ぐ無線通信装置を提供することにある。 The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a wireless communication apparatus that suppresses the intermodulation distortion of a frequency multiplier to prevent the generation of noise.
　上述した課題を解決するために、本発明は、所定の帯域幅をもった高周波信号を送信または受信するアンテナと、前記高周波信号よりも低い中心周波数のローカル信号を出力するローカル発振器と、前記ローカル信号を周波数逓倍し、前記ローカル発振器に電気的に接続された周波数逓倍器と、前記アンテナと前記周波数逓倍器とに接続されたミキサと、を備えた無線通信装置であって、前記ローカル発振器と前記周波数逓倍器との間には、前記ローカル信号を通過させ前記ローカル信号とは異なる周波数のノイズ信号を除去するフィルタが設けられ、前記フィルタは、前記ローカル信号の中心周波数と前記ノイズ信号の中心周波数との周波数差の絶対値が前記高周波信号の帯域幅よりも小さくなる関係を満たす前記ノイズ信号を除去することを特徴としている。 In order to solve the problems described above, the present invention provides an antenna for transmitting or receiving a high frequency signal having a predetermined bandwidth, a local oscillator for outputting a local signal having a lower center frequency than the high frequency signal, and the local A radio communication apparatus comprising: a frequency multiplier that frequency-multiplies a signal, and a frequency multiplier electrically connected to the local oscillator; and a mixer connected to the antenna and the frequency multiplier. A filter for passing the local signal and removing a noise signal of a frequency different from that of the local signal is provided between the frequency multiplier and the filter, and the filter is a center frequency of the local signal and a center of the noise signal. Removing the noise signal satisfying the relation that the absolute value of the frequency difference with the frequency is smaller than the bandwidth of the high frequency signal It is characterized by a door.
　本発明によれば、ローカル発振器と周波数逓倍器との間には、ローカル信号とは異なる周波数のノイズ信号を除去するフィルタが設けられている。このため、周波数逓倍器は、ノイズ信号が除去されたローカル信号のみを周波数逓倍するから、周波数逓倍器の相互変調歪みを抑制して、ノイズの発生を防ぐことができる。 According to the present invention, a filter is provided between the local oscillator and the frequency multiplier for removing noise signals of a frequency different from that of the local signal. Therefore, since the frequency multiplier frequency-multiplies only the local signal from which the noise signal has been removed, the intermodulation distortion of the frequency multiplier can be suppressed to prevent the generation of noise.
　また、ノイズ信号が混入したローカル信号を周波数逓倍器が周波数逓倍すると、不要なノイズスペクトラムが生成される。この場合、ローカル信号の中心周波数とノイズ信号の中心周波数との周波数差の絶対値が高周波信号の帯域幅よりも小さくなるときには、周波数逓倍器から出力される不要なノイズスペクトラムに基づいて、ミキサからの出力にもノイズが生成されると共に、高周波信号の帯域とノイズ帯域とが重なる。この点は、受信側のダウンコンバートを行うミキサに限らず、送信側のアップコンバートを行うミキサでも同様である。 Further, when the frequency multiplier frequency-multiplies the local signal mixed with the noise signal, an unnecessary noise spectrum is generated. In this case, when the absolute value of the frequency difference between the center frequency of the local signal and the center frequency of the noise signal is smaller than the bandwidth of the high frequency signal, the mixer generates noise based on the unnecessary noise spectrum output from the frequency multiplier. Noise is also generated at the output of the high frequency signal, and the band of the high frequency signal and the noise band overlap. This point is not limited to the mixer that performs down conversion on the reception side, and the same applies to a mixer that performs up conversion on the transmission side.
　これに対し、フィルタは、ローカル信号の中心周波数とノイズ信号の中心周波数との周波数差の絶対値が高周波信号の帯域幅よりも小さくなる関係を満たすノイズ信号を除去する。このため、通信信号帯域とノイズ帯域との重複を防ぐことができる。 On the other hand, the filter removes the noise signal that satisfies the relationship that the absolute value of the frequency difference between the center frequency of the local signal and the center frequency of the noise signal is smaller than the bandwidth of the high frequency signal. Therefore, overlapping of the communication signal band and the noise band can be prevented.
本発明の第１の実施の形態による受信装置を示すブロック図である。FIG. 1 is a block diagram showing a receiver according to a first embodiment of the present invention. 図１中のフィルタを示す回路図である。It is a circuit diagram which shows the filter in FIG. 図２中のフィルタの挿入損失の周波数特性を示す特性線図である。FIG. 5 is a characteristic diagram showing frequency characteristics of insertion loss of the filter in FIG. 2; 比較例による受信装置を示すブロック図である。It is a block diagram which shows the receiver by a comparative example. 第１の変形例によるフィルタを示す回路図である。It is a circuit diagram showing the filter by the 1st modification. 第２の変形例によるフィルタを示す回路図である。It is a circuit diagram showing the filter by the 2nd modification. 第３の変形例によるフィルタを示す回路図である。It is a circuit diagram showing the filter by the 3rd modification. 本発明の第２の実施の形態による送受信装置を示すブロック図である。It is a block diagram showing the transmitting and receiving device by a 2nd embodiment of the present invention.
　以下、本発明の実施の形態による無線通信装置を、添付図面を参照しつつ詳細に説明する。 Hereinafter, a wireless communication apparatus according to an embodiment of the present invention will be described in detail with reference to the attached drawings.
　図１は本発明の第１の実施の形態による無線通信装置としての受信装置１を示している。受信装置１は、アンテナ２、ローカル発振器３、周波数逓倍器４、ミキサ５、復調回路７、フィルタ８等を備えている。 FIG. 1 shows a receiving apparatus 1 as a wireless communication apparatus according to a first embodiment of the present invention. The receiver 1 includes an antenna 2, a local oscillator 3, a frequency multiplier 4, a mixer 5, a demodulation circuit 7, a filter 8 and the like.
　アンテナ２は、予め決められた帯域幅Ｘの高周波信号ＳHを受信する。アンテナ２は、ミキサ５に接続されている。高周波信号ＳHの中心周波数ＦHは、例えば３ＧＨｚに設定されている。また、帯域幅Ｘは、例えば３００ＭＨｚに設定されている。アンテナ２は、ミキサ５に高周波信号ＳHを入力する。なお、アンテナ２は、ミキサ５に直接的に接続されている必要はなく、例えば低雑音増幅器、帯域通過フィルタを介して間接的に接続されていてもよい。 The antenna 2 receives a high frequency signal SH of a predetermined bandwidth X. The antenna 2 is connected to the mixer 5. The center frequency FH of the high frequency signal SH is set to, for example, 3 GHz. The bandwidth X is set to, for example, 300 MHz. The antenna 2 inputs the high frequency signal SH to the mixer 5. The antenna 2 does not have to be directly connected to the mixer 5, and may be connected indirectly via, for example, a low noise amplifier or a band pass filter.
　ローカル発振器３は、高周波信号ＳHよりも低い中心周波数ＦLのローカル信号ＳLを出力する。ローカル信号ＳLの中心周波数ＦLは、例えば５００ＭＨｚに設定されている。ローカル発振器３は、周波数逓倍器４に電気的に接続されている。 The local oscillator 3 outputs a local signal SL having a center frequency FL lower than that of the high frequency signal SH. The center frequency FL of the local signal SL is set to, for example, 500 MHz. The local oscillator 3 is electrically connected to the frequency multiplier 4.
　周波数逓倍器４は、ローカル信号ＳLを周波数逓倍した信号Ｓmを出力する。具体的には、周波数逓倍器４は、中心周波数ＦLの整数倍（例えば２倍）の信号Ｓmを出力する。これにより、信号Ｓmの中心周波数Ｆmは、例えば１ＧＨｚになる。周波数逓倍器４の出力側は、ミキサ５に接続されている。なお、周波数逓倍器４は、ローカル信号ＳLの中心周波数ＦLを２倍にするものに限らず、例えば３倍にするものでもよく、４倍以上にするものでもよい。 The frequency multiplier 4 outputs a signal Sm obtained by frequency-multiplying the local signal SL. Specifically, the frequency multiplier 4 outputs a signal Sm that is an integral multiple (for example, twice) of the center frequency FL. Thus, the center frequency Fm of the signal Sm is, for example, 1 GHz. The output side of the frequency multiplier 4 is connected to the mixer 5. The frequency multiplier 4 is not limited to double the center frequency FL of the local signal SL, but may be, for example, triple or quadruple or more.
　ミキサ５は、アンテナ２と周波数逓倍器４とに接続されている。ミキサ５は、周波数逓倍器４から出力された信号Ｓmと、アンテナ２から出力された高周波信号ＳHとを合成し、合成信号Ｓcを出力する。このとき、合成信号Ｓcは、高周波信号ＳHをダウンコンバートしたダウンコンバート信号Ｓdと、高周波信号ＳHをアップコンバートしたアップコンバート信号Ｓuを含んでいる。ダウンコンバート信号Ｓdの中心周波数Ｆdは、高周波信号ＳHの中心周波数ＦHから高周波信号ＳHの中心周波数ＦHと信号Ｓmの中心周波数Ｆmとの差を減算した値として、例えば２ＧＨｚになる。一方、アップコンバート信号Ｓuの中心周波数Ｆuは、高周波信号ＳHの中心周波数ＦHから高周波信号ＳHの中心周波数ＦHと信号Ｓmの中心周波数Ｆmとの差を加算した値として、例えば４ＧＨｚになる。 The mixer 5 is connected to the antenna 2 and the frequency multiplier 4. The mixer 5 combines the signal Sm output from the frequency multiplier 4 and the high frequency signal SH output from the antenna 2 and outputs a combined signal Sc. At this time, the combined signal Sc includes a down-converted signal Sd obtained by down-converting the high-frequency signal SH and an up-converted signal Su obtained by up-converting the high-frequency signal SH. The center frequency Fd of the down-converted signal Sd is, for example, 2 GHz as a value obtained by subtracting the difference between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm from the center frequency FH of the high frequency signal SH. On the other hand, the center frequency Fu of the up-conversion signal Su is, for example, 4 GHz as a value obtained by adding the difference between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm from the center frequency FH of the high frequency signal SH.
　ミキサ５の出力側は、帯域通過フィルタ６を介して復調回路７に接続されている。帯域通過フィルタ６は、合成信号Ｓcから不要なアップコンバート信号Ｓuを除去し、ダウンコンバート信号Ｓdを復調回路７に出力する。このため、受信用のミキサ５は、高周波信号ＳHとローカル信号ＳLを周波数逓倍した信号Ｓmとを合成して、高周波信号ＳHをダウンコンバートした低周波信号（ダウンコンバート信号Ｓd）を出力するダウンコンバートミキサとして機能する。復調回路７は、例えば検波回路、ＡＤコンバータ等を含み、ダウンコンバート信号Ｓdを用いて信号を復調し、受信用のベースバンド信号を生成する。 The output side of the mixer 5 is connected to the demodulation circuit 7 via the band pass filter 6. The band pass filter 6 removes the unnecessary up-converted signal Su from the combined signal Sc, and outputs the down-converted signal Sd to the demodulation circuit 7. For this reason, the mixer 5 for reception combines the high frequency signal SH and the signal Sm obtained by frequency-multiplying the local signal SL, and outputs a low frequency signal (down converted signal Sd) obtained by down converting the high frequency signal SH. It functions as a mixer. The demodulation circuit 7 includes, for example, a detection circuit, an AD converter, and the like, demodulates the signal using the down-converted signal Sd, and generates a baseband signal for reception.
　フィルタ８は、ローカル発振器３と周波数逓倍器４との間に設けられている。フィルタ８は、ローカル信号ＳLとは異なる周波数のノイズ信号Ｎを除去する。このとき、フィルタ８は、ローカル信号ＳLの中心周波数ＦLとノイズ信号Ｎの中心周波数Ｆnとの周波数差ΔＦ（ΔＦ＝Ｆn－ＦL）の絶対値が高周波信号ＳHの帯域幅Ｘよりも小さくなる（Ｘ＞｜ΔＦ｜）関係を満たすノイズ信号Ｎを除去する。このとき、ノイズ信号Ｎは、例えば高周波信号ＳHとは異なる周波数帯の無線通信に使用される他の高周波信号ＳHnである。具体的には、ノイズ信号Ｎは、例えばＬＴＥ（Long Term Evolution）のローバンドである７００ＭＨｚ帯の信号である。 The filter 8 is provided between the local oscillator 3 and the frequency multiplier 4. The filter 8 removes the noise signal N having a frequency different from that of the local signal SL. At this time, in filter 8, the absolute value of frequency difference ΔF (ΔF = Fn−FL) between center frequency FL of local signal SL and center frequency Fn of noise signal N is smaller than bandwidth X of high frequency signal SH ( A noise signal N satisfying the relationship X> | ΔF |) is removed. At this time, the noise signal N is, for example, another high frequency signal SHn used for wireless communication of a frequency band different from that of the high frequency signal SH. Specifically, the noise signal N is, for example, a 700 MHz band signal which is a low band of LTE (Long Term Evolution).
　図２に示すように、フィルタ８は、ローカル信号ＳLを通過させてノイズ信号Ｎを除去する帯域除去フィルタ（ＢＳＦ：Band Stop Filter）によって構成されている。フィルタ８は、インダクタ素子Ｌpとキャパシタ素子Ｃpとを組み合わせて構成されている。具体的には、フィルタ８のＢＳＦは、インダクタ素子Ｌpとキャパシタ素子Ｃpとが並列接続された並列共振回路８Ａによって構成されている。このとき、フィルタ８の並列共振周波数は、ノイズ信号Ｎの中心周波数Ｆnとして例えば７００ＭＨｚに設定されている（図３参照）。 As shown in FIG. 2, the filter 8 is configured by a band removal filter (BSF: Band Stop Filter) which passes the local signal SL and removes the noise signal N. The filter 8 is configured by combining an inductor element Lp and a capacitor element Cp. Specifically, the BSF of the filter 8 is configured by a parallel resonant circuit 8A in which an inductor element Lp and a capacitor element Cp are connected in parallel. At this time, the parallel resonance frequency of the filter 8 is set to, for example, 700 MHz as the center frequency Fn of the noise signal N (see FIG. 3).
　本実施の形態による受信装置１は上述の如き構成を有するもので、次にその作動について説明する。 The receiver 1 according to the present embodiment has the above-described configuration, and its operation will be described next.
　ローカル発振器３は、ローカル信号ＳLとして、５００ＭＨｚの単一周波数（中心周波数ＦL）の正弦波信号を生成する。ローカル信号ＳLは、周波数逓倍器４で整数倍（例えば２倍）の周波数（中心周波数Ｆm）となった信号Ｓmに変換される。このとき、信号Ｓmの中心周波数Ｆmは、１ＧＨｚになる。 The local oscillator 3 generates a sine wave signal of 500 MHz single frequency (center frequency FL) as the local signal SL. The local signal SL is converted by the frequency multiplier 4 into a signal Sm which has an integral multiple (for example, double) frequency (center frequency Fm). At this time, the center frequency Fm of the signal Sm is 1 GHz.
　ここで、ミキサ５には、アンテナ２で受信した高周波信号ＳHと周波数変換された信号Ｓmが入力される。ミキサ５は、これらの高周波信号ＳHとローカル信号ＳLを周波数逓倍した信号Ｓmとを合成し、合成信号Ｓcを出力する。このとき、合成信号Ｓcには、ダウンコンバート信号Ｓdとアップコンバート信号Ｓuとが含まれている。ダウンコンバート信号Ｓdの中心周波数Ｆdは、高周波信号ＳHの中心周波数ＦHから信号Ｓmの中心周波数Ｆmを減算した値（ＦH－Ｆm）であり、２ＧＨｚである。一方、アップコンバート信号Ｓuの中心周波数Ｆuは、高周波信号ＳHの中心周波数ＦHに信号Ｓmの中心周波数Ｆmを加算した値（ＦH＋Ｆm）であり、４ＧＨｚである。また、ダウンコンバート信号Ｓdとアップコンバート信号Ｓuは、いずれも高周波信号ＳHと同じ帯域幅Ｘを有する。帯域通過フィルタ６は、合成信号Ｓcのダウンコンバート信号Ｓdとアップコンバート信号Ｓuから通信に必要な信号であるダウンコンバート信号Ｓdを選択する。帯域通過フィルタ６は、ダウンコンバート信号Ｓdを復調回路７に出力する。 Here, the high frequency signal SH received by the antenna 2 and the frequency-converted signal Sm are input to the mixer 5. The mixer 5 combines the high frequency signal SH and the signal Sm obtained by frequency-multiplying the local signal SL, and outputs a combined signal Sc. At this time, the combined signal Sc includes the down-converted signal Sd and the up-converted signal Su. The center frequency Fd of the down converted signal Sd is a value (FH−Fm) obtained by subtracting the center frequency Fm of the signal Sm from the center frequency FH of the high frequency signal SH, and is 2 GHz. On the other hand, the center frequency Fu of the up-conversion signal Su is a value (FH + Fm) obtained by adding the center frequency Fm of the signal Sm to the center frequency FH of the high frequency signal SH, which is 4 GHz. Further, the down-converted signal Sd and the up-converted signal Su both have the same bandwidth X as the high frequency signal SH. The band pass filter 6 selects a down converted signal Sd which is a signal necessary for communication from the down converted signal Sd of the combined signal Sc and the up converted signal Su. The band pass filter 6 outputs the down converted signal Sd to the demodulation circuit 7.
　ところで、無線通信装置の近傍には、アンテナ２で使用する無線通信方式とは異なる無線通信方式のアンテナ１０が配置されることがある（図４参照）。このとき、アンテナ１０は、アンテナ２とは独立して無線通信を行い、電波を放出する。このため、アンテナ２による高周波信号ＳHの受信と、アンテナ１０からの電波（高周波信号ＳHn）の放出が同時に行われることがある。この状態は、例えばスマートフォンのような小型の無線端末で発生し易い。 By the way, the antenna 10 of the wireless communication system different from the wireless communication system used by the antenna 2 may be arrange | positioned in the vicinity of a wireless communication apparatus (refer FIG. 4). At this time, the antenna 10 performs wireless communication independently of the antenna 2 and emits radio waves. Therefore, the reception of the high frequency signal SH by the antenna 2 and the emission of the radio wave (the high frequency signal SHn) from the antenna 10 may be performed simultaneously. This state is likely to occur, for example, in a small wireless terminal such as a smartphone.
　例えばスマートフォンの場合、無線ＬＡＮ（Local Area Network）とＬＴＥとの２つの通信方式を使用している。このため、異なる無線通信方式のアンテナとして、無線ＬＡＮ用とＬＴＥ用の２つのアンテナを備えている。また、小型形状であるためアンテナの実装スペースが制約され、通信方式の異なる２つのアンテナが近接して配置されている。これに加えて、通信距離を確保するため、各アンテナは数ｄＢ～３０ｄＢ程度の高出力電波を放出している。 For example, in the case of a smartphone, two communication methods of wireless LAN (Local Area Network) and LTE are used. Therefore, two antennas for wireless LAN and LTE are provided as antennas for different wireless communication methods. In addition, because of the small size, the mounting space of the antenna is restricted, and two antennas of different communication schemes are arranged in close proximity. In addition to this, each antenna emits high-output radio waves of several dB to about 30 dB in order to secure a communication distance.
　このように、スマートフォンでは、一方の無線通信方式のアンテナ１０が、他方の無線通信方式の無線通信装置に近接して配置される。これに加え、それぞれのアンテナ２，１０が高出力の電波を放出する。このため、無線通信装置の高周波成分にアンテナ１０の無線電波が結合し、ローカル信号ＳLの信号線、即ちローカル発振器３と周波数逓倍器４との間の信号線にアンテナ１０の無線電波がノイズ信号Ｎとして侵入することがある。このとき、ＬＴＥのローバンドの中心周波数は、７００ＭＨｚであり、ローカル信号ＳLの中心周波数ＦLである５００ＭＨｚに近い。 As described above, in the smartphone, the antenna 10 of one wireless communication scheme is disposed in proximity to the wireless communication device of the other wireless communication scheme. In addition to this, the respective antennas 2 and 10 emit radio waves of high power. Therefore, the radio wave of the antenna 10 is coupled to the high frequency component of the radio communication device, and the radio wave of the antenna 10 is a noise signal on the signal line of the local signal SL, ie, the signal line between the local oscillator 3 and the frequency multiplier 4 It may invade as N. At this time, the center frequency of the LTE low band is 700 MHz, which is close to 500 MHz which is the center frequency FL of the local signal SL.
　つまり、ローカル信号ＳLの信号線には、本来のローカル信号ＳLに加えて、アンテナ１０から放出された高周波信号ＳHn（７００ＭＨｚの信号）がノイズ信号Ｎとなって伝導することになる。ここでは、ノイズ信号Ｎの中心周波数Ｆnがローカル信号ＳLの中心周波数ＦLよりも高い場合（Ｆn＞ＦL）について説明する。以下に述べる課題は、ノイズ信号Ｎの中心周波数Ｆnがローカル信号ＳLの中心周波数ＦLよりも低い場合（Ｆn＜ＦL）でも同様に発生する。 That is, in addition to the original local signal SL, the high frequency signal SHn (a signal of 700 MHz) emitted from the antenna 10 is conducted as a noise signal N to the signal line of the local signal SL. Here, the case where the center frequency Fn of the noise signal N is higher than the center frequency FL of the local signal SL (Fn> FL) will be described. The problems described below also occur when the center frequency Fn of the noise signal N is lower than the center frequency FL of the local signal SL (Fn <FL).
　図４は、比較例による受信装置１１として、本発明のフィルタ８を省いた構成を示している。この比較例の受信装置１１では、本来のローカル信号ＳLに、アンテナ１０から伝搬したノイズ信号Ｎが混入した信号ＳLnが周波数逓倍器４に入力される。ここで、周波数逓倍器４が正常動作するには、単一周波数の信号が入力される必要がある。しかしながら、比較例のように、本来のローカル信号ＳLにノイズ信号Ｎを含んだ信号ＳLnが周波数逓倍器４に入力されると、単一周波数ではなく２つの周波数をもった信号ＳLnが入力されることになる。 FIG. 4 shows a configuration in which the filter 8 of the present invention is omitted as the receiving device 11 according to the comparative example. In the receiving apparatus 11 of this comparative example, a signal SLn in which the noise signal N propagated from the antenna 10 is mixed into the original local signal SL is input to the frequency multiplier 4. Here, in order for the frequency multiplier 4 to operate normally, a single frequency signal needs to be input. However, as in the comparative example, when the signal SLn including the noise signal N in the original local signal SL is input to the frequency multiplier 4, the signal SLn having two frequencies instead of a single frequency is input. It will be.
　このとき、周波数逓倍器４では、相互変調が起こる。この相互変調は非線形性を示すため、高次の相互変調歪が生成される。図４では、高次の相互変調歪のうち、２次の相互変調歪の例を示した。つまり、周波数逓倍器４を通過した後の信号Ｓmnは、本来のローカル信号ＳLが周波数逓倍された信号Ｓmと、相互変調で生じる不要なノイズスペクトラム(Ｎ1およびＮ2)を含んでいる。 At this time, intermodulation occurs in the frequency multiplier 4. Since this intermodulation exhibits non-linearity, high-order intermodulation distortion is generated. FIG. 4 shows an example of second-order intermodulation distortion among higher-order intermodulation distortion. That is, the signal Smn after passing through the frequency multiplier 4 includes the signal Sm obtained by frequency-multiplying the original local signal SL and the unnecessary noise spectrum (N1 and N2) generated by the intermodulation.
　信号Ｓmnに含まれるノイズＮ1の周波数は、信号Ｓmの中心周波数Ｆmからノイズ信号Ｎの中心周波数Ｆnとローカル信号ＳLの中心周波数ＦLとの差（Ｆn－ＦL）を減算した値｛Ｆm－（Ｆn－ＦL）｝になり、例えば８００ＭＨｚになる。また、信号Ｓmnに含まれるノイズＮ2の周波数は、信号Ｓmの中心周波数Ｆmからノイズ信号Ｎの中心周波数Ｆnとローカル信号ＳLの中心周波数ＦLとの差（Ｆn－ＦL）を加算した値｛Ｆm＋（Ｆn－ＦL）｝になり、例えば１．２ＧＨｚになる。この不要なノイズスペクトラムを含んだ信号Ｓmnがミキサ５に入力され、アンテナ２で受信した高周波信号ＳHと信号合成される。 The frequency of the noise N1 included in the signal Smn is a value obtained by subtracting the difference (Fn−FL) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL from the center frequency Fm of the signal Sm {Fm− (Fn -FL)}, for example 800 MHz. Further, the frequency of the noise N2 included in the signal Smn is a value {Fm + (sum of difference (Fn−FL) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL from the center frequency Fm of the signal Sm). Fn-FL)}, for example 1.2 GHz. The signal Smn including the unnecessary noise spectrum is input to the mixer 5 and is signal-combined with the high frequency signal SH received by the antenna 2.
　このとき、ミキサ５を通過した後の合成信号Ｓcnには、本来の通信信号であるダウンコンバート信号Ｓdやアップコンバート信号Ｓuに加えて、ノイズＮ3～Ｎ6が発生する。ノイズＮ3，Ｎ4は、ダウンコンバート信号Ｓdの周辺帯域に発生する。ノイズＮ5，Ｎ6は、アップコンバート信号Ｓuの周辺帯域に発生する。 At this time, in the combined signal Scn after passing through the mixer 5, noises N3 to N6 are generated in addition to the down-converted signal Sd and the up-converted signal Su which are the original communication signals. Noises N3 and N4 occur in the peripheral band of the down-converted signal Sd. Noises N5 and N6 occur in the peripheral band of the up-converted signal Su.
　ここで、ノイズＮ3の中心周波数は、高周波信号ＳHの中心周波数ＦHと本来のローカル信号ＳLが周波数逓倍された信号Ｓmの中心周波数Ｆmとの差（ＦH－Ｆm）からノイズ信号Ｎの中心周波数Ｆnとローカル信号ＳLの中心周波数ＦLとの差（Ｆn－ＦL）を減算した値｛（ＦH－Ｆm）－（Ｆn－ＦL）｝になり、例えば１．８ＧＨｚになる。このとき、例えば、ノイズＮ3は、高周波信号ＳHと同じ帯域幅Ｘを有する。 Here, the center frequency of the noise N3 is the difference between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm obtained by frequency multiplication of the original local signal SL (FH−Fm) to the center frequency Fn of the noise signal N And the value (FH−Fm) − (Fn−FL)} obtained by subtracting the difference (Fn−FL) between the local signal SL and the center frequency FL of the local signal SL, for example, 1.8 GHz. At this time, for example, the noise N3 has the same bandwidth X as the high frequency signal SH.
　ノイズＮ4の中心周波数は、高周波信号ＳHの中心周波数ＦHと信号Ｓmの中心周波数Ｆmとの差（ＦH－Ｆm）に、ノイズ信号Ｎの中心周波数Ｆnとローカル信号ＳLの中心周波数ＦLとの差（Ｆn－ＦL）を加算した値｛（ＦH－Ｆm）＋（Ｆn－ＦL）｝になり、例えば２．２ＧＨｚになる。このとき、例えば、ノイズＮ4は、高周波信号ＳHと同じ帯域幅Ｘを有する。 The center frequency of the noise N4 is the difference (FH−Fm) between the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm, and the difference between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL The sum of Fn−FL) is {(FH−Fm) + (Fn−FL)}, for example, 2.2 GHz. At this time, for example, the noise N4 has the same bandwidth X as the high frequency signal SH.
　また、ノイズＮ5の中心周波数は、高周波信号ＳHの中心周波数ＦHと信号Ｓmの中心周波数Ｆmとの和（ＦH＋Ｆm）からノイズ信号Ｎの中心周波数Ｆnとローカル信号ＳLの中心周波数ＦLとの差（Ｆn－ＦL）を減算した値｛（ＦH＋Ｆm）－（Ｆn－ＦL）｝になり、例えば３．８ＧＨｚになる。このとき、例えば、ノイズＮ5は、高周波信号ＳHと同じ帯域幅Ｘを有する。 The center frequency of the noise N5 is the sum (FH + Fm) of the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm to the difference (Fn) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL. The value obtained by subtracting −FL) is {(FH + Fm) − (Fn−FL)}, for example, 3.8 GHz. At this time, for example, the noise N5 has the same bandwidth X as the high frequency signal SH.
　ノイズＮ6の中心周波数は、高周波信号ＳHの中心周波数ＦHと信号Ｓmの中心周波数Ｆmとの和（ＦH＋Ｆm）に、ノイズ信号Ｎの中心周波数Ｆnとローカル信号ＳLの中心周波数ＦLとの差（Ｆn－ＦL）を加算した値｛（ＦH＋Ｆm）＋（Ｆn－ＦL）｝になり、例えば４．２ＧＨｚになる。このとき、ノイズＮ6は、例えば、高周波信号ＳHと同じ帯域幅Ｘを有する。 The center frequency of the noise N6 is the sum (FH + Fm) of the center frequency FH of the high frequency signal SH and the center frequency Fm of the signal Sm, and the difference (Fn−) between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL. It becomes the value {(FH + Fm) + (Fn-FL)} which added FL) and becomes 4.2 GHz, for example. At this time, the noise N6 has, for example, the same bandwidth X as the high frequency signal SH.
　図４より明らかなように、帯域幅Ｘが、ローカル信号ＳLの信号線に侵入するノイズ信号Ｎの中心周波数Ｆnと本来のローカル信号ＳLの中心周波数ＦLとの差分より大きいとき、つまり、Ｘ＞（Ｆn－ＦL）の関係であるとき、本来の通信信号の帯域にノイズ帯域が重なる。 As apparent from FIG. 4, when the bandwidth X is larger than the difference between the center frequency Fn of the noise signal N entering the signal line of the local signal SL and the center frequency FL of the original local signal SL, that is, X> When (Fn−FL), the noise band overlaps with the band of the original communication signal.
　同様に、ノイズ信号Ｎの中心周波数Ｆnが本来のローカル信号ＳLの中心周波数ＦLよりも低いとき（Ｆn＜ＦL）には、Ｘ＞（ＦL－Ｆn）の関係であるとき、本来の通信信号の帯域にノイズ帯域が重なる。即ち、帯域幅Ｘが、ノイズ信号Ｎの中心周波数Ｆnとローカル信号ＳLの中心周波数ＦLとの周波数差ΔＦの絶対値よりも大きいとき（Ｘ＞｜Ｆn－ＦL｜）、本来の通信信号の帯域にノイズ帯域が重なる。 Similarly, when the center frequency Fn of the noise signal N is lower than the center frequency FL of the original local signal SL (Fn <FL), when X> (FL−Fn), the original communication signal is The noise band overlaps the band. That is, when the bandwidth X is larger than the absolute value of the frequency difference ΔF between the center frequency Fn of the noise signal N and the center frequency FL of the local signal SL (X> | Fn−FL |), the band of the original communication signal Noise band overlaps the
　この関係が成り立つときには、本来の通信信号の帯域にノイズ帯域が重なった合成信号Ｓmnが、受信側の復調回路７等のようなＩＣ（集積回路）に伝送される。このとき、受信側のＩＣで合成信号Ｓmnに基づいてデータが復調される。但し、ミキサ５と復調回路７の間に設けられた帯域通過フィルタ６は、合成信号Ｓmnからアップコンバート信号ＳuおよびノイズＮ5，Ｎ6を除去する。このため、受信側のＩＣには、ダウンコンバート信号Ｓdに加えて、ノイズＮ3，Ｎ4が入力される。 When this relationship holds, the composite signal Smn in which the noise band overlaps the band of the original communication signal is transmitted to an IC (integrated circuit) such as the demodulation circuit 7 on the reception side. At this time, data is demodulated based on the combined signal Smn in the IC on the receiving side. However, the band pass filter 6 provided between the mixer 5 and the demodulation circuit 7 removes the up-converted signal Su and the noises N5 and N6 from the combined signal Smn. Therefore, in addition to the down-converted signal Sd, noises N3 and N4 are inputted to the IC on the receiving side.
　このとき、受信側のＩＣは、ノイズＮ3，Ｎ4により異なったデータ配列やデータパターンとして、高周波信号ＳHの内容を認識する。即ち、受信側のＩＣは、高周波信号ＳHに基づくダウンコンバート信号Ｓdが入力されたときでも、ノイズＮ3，Ｎ4によって、高周波信号ＳHの内容を誤ったデータとして認識する。このように正常な通信信号を受け取れないとき、受信側のＩＣは、送信側に対して、データの再送信を要求する。この再送信が繰り返し発生することで、アンテナ２での通信速度が低下し、最悪の場合には通信不能に至る。 At this time, the IC on the receiving side recognizes the content of the high frequency signal SH as a data arrangement or data pattern which is different due to the noises N3 and N4. That is, even when the down-converted signal Sd based on the high frequency signal SH is input, the IC on the receiving side recognizes the content of the high frequency signal SH as erroneous data by the noises N3 and N4. As described above, when a normal communication signal can not be received, the IC on the receiving side requests the transmitting side to retransmit data. Repeated occurrence of this re-transmission reduces the communication speed at the antenna 2, and in the worst case, the communication becomes impossible.
　これに対し、本実施の形態では、ローカル発振器３と周波数逓倍器４との間に、ローカル信号ＳL以外のノイズ信号Ｎを除去するフィルタ９を設けた。このため、アンテナ１０の無線電波（７００ＭＨｚ帯の高周波信号）がローカル発振器３と周波数逓倍器４とを繋ぐ信号線に侵入したとしても、フィルタ９によって、その無線周波数帯でノイズ信号Ｎを抑制することができる。この結果、周波数逓倍器４には、ノイズ信号Ｎが入力されなくなる。このようにノイズ信号Ｎの周波数帯が予め分かっている場合には、アンテナ１０の無線周波数帯（例えば７００ＭＨｚ帯）でノイズ抑制可能な帯域除去フィルタを構成するのが好ましい。一方で、本来のローカル信号ＳLは通信に必要な信号であるため、フィルタ８は、ローカル信号ＳLへの影響をなくす必要がある。よって、フィルタ８は、本来のローカル信号ＳLの周波数帯では帯域通過フィルタの機能を有する必要がある。 On the other hand, in the present embodiment, the filter 9 for removing the noise signal N other than the local signal SL is provided between the local oscillator 3 and the frequency multiplier 4. Therefore, even if the radio wave (high frequency signal of 700 MHz band) of the antenna 10 intrudes into the signal line connecting the local oscillator 3 and the frequency multiplier 4, the filter 9 suppresses the noise signal N in the radio frequency band. be able to. As a result, the noise signal N is not input to the frequency multiplier 4. Thus, when the frequency band of the noise signal N is known in advance, it is preferable to configure a band elimination filter that can suppress noise in the radio frequency band (for example, 700 MHz band) of the antenna 10. On the other hand, since the original local signal SL is a signal necessary for communication, the filter 8 needs to eliminate the influence on the local signal SL. Therefore, the filter 8 needs to have the function of a band pass filter in the frequency band of the original local signal SL.
　図２に、本実施の形態によるフィルタ８の構成を示す。本実施の形態によるフィルタ８は、インダクタ素子Ｌpとキャパシタ素子Ｃpとを並列接続したＬＣフィルタによって構成されている。このとき、インダクタ素子Ｌpのインダクタンスは、例えば６ｎＨとし、キャパシタ素子Ｃpのキャパシタンスは８ｐＦとした。なお、これらの具体的な数値は、本来のローカル信号ＳLの中心周波数ＦLとノイズ信号Ｎの中心周波数Ｆnに応じて適宜設定される。具体的には、本来のローカル信号ＳLの中心周波数ＦLでは低損失となり、ノイズ信号Ｎの中心周波数Ｆnで高損失となるように、インダクタ素子Ｌpのインダクタンスおよびキャパシタ素子Ｃpのキャパシタンスは適宜選択される。図３に、図２中のフィルタ８による挿入損失の周波数特性を示す。図３に示すように、本実施の形態によるフィルタ８（ＬＣフィルタ）の挿入損失は、本来のローカル信号ＳLの中心周波数ＦLである５００ＭＨｚでは０．５ｄＢであり、ノイズ信号Ｎの中心周波数Ｆnである７００ＭＨｚでは１１ｄＢとなっている。 FIG. 2 shows the configuration of the filter 8 according to the present embodiment. The filter 8 according to the present embodiment is constituted by an LC filter in which an inductor element Lp and a capacitor element Cp are connected in parallel. At this time, the inductance of the inductor element Lp is, for example, 6 nH, and the capacitance of the capacitor element Cp is 8 pF. Note that these specific numerical values are appropriately set according to the original center frequency FL of the local signal SL and the center frequency Fn of the noise signal N. Specifically, the inductance of the inductor element Lp and the capacitance of the capacitor element Cp are appropriately selected so that the loss is low at the center frequency FL of the local signal SL and is high loss at the center frequency Fn of the noise signal N. . FIG. 3 shows the frequency characteristic of the insertion loss by the filter 8 in FIG. As shown in FIG. 3, the insertion loss of the filter 8 (LC filter) according to the present embodiment is 0.5 dB at 500 MHz which is the center frequency FL of the original local signal SL, and at the center frequency Fn of the noise signal N. It is 11 dB at a certain 700 MHz.
　図２に示したフィルタ８を、ローカル発振器３と周波数逓倍器４を繋ぐ信号線に挿入して、通信試験を実施した。その結果、フィルタ８の挿入前はアンテナ２での無線通信は不能であったのに対し、本実施の形態によるフィルタ８の挿入後は通信可能となった。また、通信速度も本来のデータ転送スピードであることを確認した。 A communication test was performed by inserting the filter 8 shown in FIG. 2 into a signal line connecting the local oscillator 3 and the frequency multiplier 4. As a result, while radio communication at the antenna 2 was impossible before the insertion of the filter 8, communication became possible after the insertion of the filter 8 according to the present embodiment. It was also confirmed that the communication speed was also the original data transfer speed.
　かくして、本実施の形態では、ローカル発振器３と周波数逓倍器４との間には、ローカル信号ＳLとは異なる周波数のノイズ信号Ｎを除去するフィルタ８を設けた。このため、周波数逓倍器４は、ノイズ信号Ｎが除去されたローカル信号ＳLを周波数逓倍するから、周波数逓倍器４の相互変調歪みを抑制して、ノイズの発生を防ぐことができる。 Thus, in the present embodiment, a filter 8 is provided between the local oscillator 3 and the frequency multiplier 4 for removing the noise signal N having a frequency different from that of the local signal SL. For this reason, the frequency multiplier 4 frequency-multiplies the local signal SL from which the noise signal N has been removed, so intermodulation distortion of the frequency multiplier 4 can be suppressed and generation of noise can be prevented.
　また、ノイズ信号Ｎが混入したローカル信号ＳLを周波数逓倍器４が周波数逓倍すると、不要なノイズスペクトラムが生成される。この場合、ローカル信号ＳLの中心周波数ＦLとノイズ信号Ｎの中心周波数Ｆnとの周波数差ΔＦ（ΔＦ＝Ｆn－ＦL）の絶対値が高周波信号ＳHの帯域幅Ｘよりも小さくなる（Ｘ＞｜ΔＦ｜）関係を満たすときには、周波数逓倍器４から出力される不要なノイズスペクトラムに基づいて、ミキサ５からの出力にもノイズが生成されると共に、高周波信号ＳHの帯域とノイズ帯域とが重なる。 When the frequency multiplier 4 frequency-multiplies the local signal SL mixed with the noise signal N, an unnecessary noise spectrum is generated. In this case, the absolute value of the frequency difference ΔF (ΔF = Fn−FL) between the center frequency FL of the local signal SL and the center frequency Fn of the noise signal N is smaller than the bandwidth X of the high frequency signal SH (X> | ΔF When the relationship |) is satisfied, noise is also generated in the output from the mixer 5 based on the unnecessary noise spectrum output from the frequency multiplier 4, and the band of the high frequency signal SH and the noise band overlap.
　これに対し、フィルタ８は、ローカル信号ＳLの中心周波数ＦLとノイズ信号Ｎの中心周波数Ｆnとの周波数差ΔＦの絶対値が高周波信号ＳHの帯域幅Ｘよりも小さくなる関係を満たすノイズ信号Ｎを除去する。このため、ミキサ５から出力されるノイズを抑制することができ、通信信号帯域とノイズ帯域との重複を防ぐことができる。 On the other hand, the filter 8 satisfies the noise signal N satisfying the relationship that the absolute value of the frequency difference .DELTA.F between the center frequency FL of the local signal SL and the center frequency Fn of the noise signal N is smaller than the bandwidth X of the high frequency signal SH. Remove. For this reason, the noise output from the mixer 5 can be suppressed, and overlapping of the communication signal band and the noise band can be prevented.
　なお、周波数差ΔＦの絶対値が高周波信号ＳHの帯域幅Ｘよりも大きくなるノイズ信号については、必ずしも除去する必要はない。このようなノイズ信号に基づいてミキサがノイズを生成しても、通信信号帯域とノイズ帯域とは重複せず、通信信号（例えばダウンコンバート信号Ｓd）とノイズとの周波数帯域が相互に分離される。このため、ミキサ５が生成したノイズは、例えば帯域通過フィルタ等によって除去することができる。 The noise signal whose absolute value of the frequency difference ΔF is larger than the bandwidth X of the high frequency signal SH need not necessarily be removed. Even if the mixer generates noise based on such noise signals, the communication signal band and the noise band do not overlap, and the frequency bands of the communication signal (for example, the down-converted signal Sd) and the noise are mutually separated. . Therefore, the noise generated by the mixer 5 can be removed by, for example, a band pass filter or the like.
　また、ノイズ信号Ｎの周波数帯域が予め既知であるから、フィルタ８を帯域除去フィルタによって構成することができる。この場合、帯域除去フィルタは、ローカル信号ＳLの中心周波数ＦLでは低損失となり、ノイズ信号Ｎの中心周波数Ｆnで高損失となるように、構成される。これにより、帯域除去フィルタからなるフィルタ８は、ローカル信号ＳLを通過させて、ノイズ信号Ｎを除去することができる。これに加え、フィルタ８は、インダクタ素子Ｌpとキャパシタ素子Ｃpとを組み合わせて構成されているから、受動素子を用いて簡易にフィルタ８を構成することができる。 Further, since the frequency band of the noise signal N is known in advance, the filter 8 can be configured by a band elimination filter. In this case, the band elimination filter is configured to have a low loss at the center frequency FL of the local signal SL and a high loss at the center frequency Fn of the noise signal N. As a result, the filter 8 including the band elimination filter can pass the local signal SL and can remove the noise signal N. In addition to this, since the filter 8 is configured by combining the inductor element Lp and the capacitor element Cp, the filter 8 can be easily configured using a passive element.
　本実施の形態では、フィルタ８の帯域除去フィルタは、インダクタ素子Ｌpとキャパシタ素子Ｃpとの並列共振回路８Ａを含んで構成されている。このため、並列共振回路８Ａの共振周波数をノイズ信号Ｎの中心周波数Ｆnに合わせることによって、中心周波数Ｆnの帯域で信号の減衰を大きくすることができ、他の帯域では、信号の減衰を小さくすることができる。このため、ローカル信号ＳLの中心周波数ＦLとノイズ信号Ｎの中心周波数Ｆnとが近いときでも、フィルタ８は、ローカル信号ＳLを通過させて、ノイズ信号Ｎを除去することができる。 In the present embodiment, the band elimination filter of the filter 8 is configured to include the parallel resonant circuit 8A of the inductor element Lp and the capacitor element Cp. Therefore, by setting the resonance frequency of the parallel resonance circuit 8A to the center frequency Fn of the noise signal N, the signal attenuation can be increased in the band of the center frequency Fn, and the signal attenuation is reduced in the other bands. be able to. Therefore, even when the center frequency FL of the local signal SL and the center frequency Fn of the noise signal N are close to each other, the filter 8 can pass the local signal SL to remove the noise signal N.
　さらに、ノイズ信号Ｎは高周波信号ＳHとは異なる周波数帯の無線通信に使用される他の高周波信号ＳHnであるから、他の高周波信号ＳHnがローカル信号ＳLに近い中心周波数を有するときでも、他の高周波信号ＳHnによるノイズを抑制することができる。 Furthermore, since the noise signal N is another high frequency signal SHn used for wireless communication of a frequency band different from the high frequency signal SH, even when the other high frequency signal SHn has a center frequency close to the local signal SL Noise due to the high frequency signal SHn can be suppressed.
　なお、前記第１の実施の形態では、フィルタ８は、１段の並列共振回路８Ａからなる帯域除去フィルタによって構成するものとした。本発明はこれに限らず、例えば図５に示す第１の変形例によるフィルタ２１のように、２段の並列共振回路２１Ａ，２１Ｂからなる帯域除去フィルタによって構成してもよい。この場合、２つの並列共振回路２１Ａ，２１Ｂの接続点とグランドとの間には、インダクタ素子Ｌaとキャパシタ素子Ｃaとが直列接続された直列回路２１Ｃが接続されている。同様に、フィルタは、３段以上の並列共振回路からなる帯域除去フィルタによって構成してもよい。 In the first embodiment, the filter 8 is constituted by a band elimination filter composed of one stage of parallel resonance circuit 8A. The present invention is not limited to this, and may be configured by a band elimination filter including two stages of parallel resonant circuits 21A and 21B, for example, as a filter 21 according to a first modification shown in FIG. In this case, a series circuit 21C in which an inductor element La and a capacitor element Ca are connected in series is connected between the connection point of the two parallel resonant circuits 21A and 21B and the ground. Similarly, the filter may be constituted by a band elimination filter consisting of three or more stages of parallel resonant circuits.
　また、図６に示す第２の変形例によるフィルタ２２のように、インダクタ素子Ｌsとキャパシタ素子Ｃsが直列接続された直列共振回路２２Ａからなる帯域通過フィルタ（ＢＰＦ：Band Pass Filter）によって構成してもよい。この場合、直列共振回路２２Ａの共振周波数がローカル信号ＳLの中心周波数ＦLに合うように、インダクタ素子Ｌsのインダクタンスおよびキャパシタ素子Ｃsのキャパシタンスがそれぞれ設定される。 Further, as in the filter 22 according to the second modification shown in FIG. 6, it is constituted by a band pass filter (BPF: Band Pass Filter) comprising a series resonant circuit 22A in which an inductor element Ls and a capacitor element Cs are connected in series. It is also good. In this case, the inductance of the inductor element Ls and the capacitance of the capacitor element Cs are set such that the resonance frequency of the series resonant circuit 22A matches the center frequency FL of the local signal SL.
　さらに、例えば図７に示す第３の変形例によるフィルタ２３のように、２段の直列共振回路２３Ａ，２３Ｂからなる帯域通過フィルタによって構成してもよい。この場合、２つの直列共振回路２３Ａ，２３Ｂの接続点とグランドとの間には、インダクタ素子Ｌbとキャパシタ素子Ｃbとが並列接続された並列回路２３Ｃが接続されている。同様に、フィルタは、３段以上の直列共振回路からなる帯域通過フィルタによって構成してもよい。 Furthermore, for example, as in the case of the filter 23 according to the third modification shown in FIG. 7, it may be configured by a band pass filter composed of two-stage series resonant circuits 23A and 23B. In this case, a parallel circuit 23C in which the inductor element Lb and the capacitor element Cb are connected in parallel is connected between the connection point of the two series resonant circuits 23A and 23B and the ground. Similarly, the filter may be constituted by a band pass filter consisting of three or more stages of series resonant circuits.
　次に、図８は本発明の第２の実施の形態を示している。第２の実施の形態の特徴は、無線通信装置として、高周波信号の送信と受信の両方を行う送受信装置に適用したことにある。第２の実施の形態では、前述した第１の実施の形態と同様の構成要素に同一の符号を付し、その説明を省略するものとする。 Next, FIG. 8 shows a second embodiment of the present invention. The feature of the second embodiment is that it is applied to a transmitting / receiving apparatus which performs both transmission and reception of high frequency signals as a wireless communication apparatus. In the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof will be omitted.
　送受信装置３１は、第１の実施の形態と同様に、アンテナ２、ローカル発振器３、周波数逓倍器４、受信用のミキサ５、復調回路７、フィルタ８を備えている。これに加え、送受信装置３１は、変調回路３２、送信用のミキサ３３を備えている。 The transmitting and receiving apparatus 31 includes an antenna 2, a local oscillator 3, a frequency multiplier 4, a mixer 5 for reception, a demodulation circuit 7, and a filter 8 as in the first embodiment. In addition to this, the transmission and reception apparatus 31 includes a modulation circuit 32 and a mixer 33 for transmission.
　送受信装置３１の受信側部分は、第１の実施の形態による受信装置１とほぼ同様に構成されている。このため、アンテナ２によって受信した高周波信号ＳHrは、受信用のミキサ５によって、ローカル信号ＳLを周波数逓倍した信号Ｓmと合成される。これにより、ミキサ５は、アップコンバート信号とダウンコンバート信号とを含む合成信号Ｓcrを出力する。合成信号Ｓcrのうちアップコンバート信号は、帯域通過フィルタ６によって除去される。このため、復調回路７は、高周波信号ＳHrをダウンコンバートした低周波信号（ダウンコンバート信号）に基づき、信号を復調する。 The receiving side portion of the transmission / reception device 31 is configured substantially the same as the reception device 1 according to the first embodiment. Therefore, the high frequency signal SHr received by the antenna 2 is combined with the signal Sm obtained by frequency-multiplying the local signal SL by the reception mixer 5. Thereby, the mixer 5 outputs the synthesized signal Scr including the up-converted signal and the down-converted signal. The up-conversion signal of the synthesized signal Scr is removed by the band pass filter 6. Therefore, the demodulation circuit 7 demodulates the signal based on the low frequency signal (down converted signal) obtained by down converting the high frequency signal SHr.
　送受信装置３１の送信側部分は、変調回路３２、送信用のミキサ３３等によって構成されている。変調回路３２は、例えばＤＡコンバータ等を含み、送信用のデータに基づいて、中間周波信号Ｓi（低周波信号）を生成する。このとき、中間周波信号Ｓiの中心周波数は、例えば２ＧＨｚに設定されている。中間周波信号Ｓiは、所定の帯域幅Ｘ（例えば３００ＭＨｚ）を有している。 The transmission side portion of the transmission and reception apparatus 31 is configured by a modulation circuit 32, a mixer 33 for transmission, and the like. The modulation circuit 32 includes, for example, a DA converter, and generates an intermediate frequency signal Si (low frequency signal) based on data for transmission. At this time, the center frequency of the intermediate frequency signal Si is set to 2 GHz, for example. The intermediate frequency signal Si has a predetermined bandwidth X (for example, 300 MHz).
　ミキサ３３は、アンテナ２と周波数逓倍器４とに接続されている。これに加えて、ミキサ３３は、変調回路３２に接続されている。送信用のミキサ３３は、受信用のミキサ５とほぼ同様に構成されている。ミキサ３３は、周波数逓倍器４から出力された信号Ｓmと、変調回路３２から出力された中間周波信号Ｓiとを合成し、合成信号Ｓctを出力する。このとき、合成信号Ｓctは、中間周波信号Ｓiをダウンコンバートしたダウンコンバート信号と、中間周波信号Ｓiをアップコンバートしたアップコンバート信号を含んでいる。ダウンコンバート信号の中心周波数は、中間周波信号Ｓiの中心周波数から中間周波信号Ｓiの中心周波数と信号Ｓmの中心周波数Ｆmとの差を減算した値として、例えば１ＧＨｚになる。一方、アップコンバート信号の中心周波数は、中間周波信号Ｓiの中心周波数から中間周波信号Ｓiの中心周波数と信号Ｓmの中心周波数Ｆmとの差を加算した値として、例えば３ＧＨｚになる。ダウンコンバート信号およびアップコンバート信号は、いずれも帯域幅Ｘを有している。 The mixer 33 is connected to the antenna 2 and the frequency multiplier 4. In addition to this, the mixer 33 is connected to the modulation circuit 32. The transmission mixer 33 is configured substantially the same as the reception mixer 5. The mixer 33 combines the signal Sm output from the frequency multiplier 4 with the intermediate frequency signal Si output from the modulation circuit 32, and outputs a combined signal Sct. At this time, the combined signal Sct includes a down-converted signal obtained by down-converting the intermediate frequency signal Si and an up-converted signal obtained by up-converting the intermediate frequency signal Si. The center frequency of the down-converted signal is, for example, 1 GHz as a value obtained by subtracting the difference between the center frequency of the intermediate frequency signal Si and the center frequency Fm of the signal Sm from the center frequency of the intermediate frequency signal Si. On the other hand, the center frequency of the up-conversion signal is, for example, 3 GHz as a value obtained by adding the difference between the center frequency of the intermediate frequency signal Si and the center frequency Fm of the signal Sm from the center frequency of the intermediate frequency signal Si. Both the downconverted signal and the upconverted signal have a bandwidth X.
　ミキサ３３は、帯域通過フィルタ３４を介してアンテナ２に接続されている。帯域通過フィルタ３４は、合成信号Ｓctから不要なダウンコンバート信号を除去し、アップコンバート信号をアンテナ２に出力する。このため、送信用のミキサ３３は、中間周波信号Ｓi（低周波信号）とローカル信号ＳLを周波数逓倍した信号Ｓmとを合成して、中間周波信号Ｓiをアップコンバートした高周波信号ＳHtを出力するアップコンバートミキサとして機能する。アンテナ２は、高周波信号ＳHtを送信する。このとき、フィルタ８は、ローカル信号ＳLの中心周波数ＦLとノイズ信号Ｎの中心周波数Ｆnとの周波数差ΔＦの絶対値が高周波信号ＳHtの帯域幅Ｘよりも小さくなる関係を満たすノイズ信号Ｎを除去する。 The mixer 33 is connected to the antenna 2 via the band pass filter 34. The band pass filter 34 removes unnecessary down-converted signals from the combined signal Sct, and outputs the up-converted signal to the antenna 2. Therefore, the transmission mixer 33 combines the intermediate frequency signal Si (low frequency signal) and the signal Sm obtained by frequency-multiplying the local signal SL, and outputs a high frequency signal SHt obtained by up-converting the intermediate frequency signal Si. It functions as a conversion mixer. The antenna 2 transmits a high frequency signal SHt. At this time, the filter 8 removes the noise signal N satisfying the relation that the absolute value of the frequency difference ΔF between the center frequency FL of the local signal SL and the center frequency Fn of the noise signal N is smaller than the bandwidth X of the high frequency signal SHt. Do.
　なお、アンテナ２と帯域通過フィルタ３４との間には、高周波信号ＳHtを電力増幅する電力増幅器を設けてもよい。また、アンテナ２とミキサ５，３３の間には、送信用と受信用で信号を分離させるために、例えばアンテナ共用器、サーキュレータ等を設けてもよい。 A power amplifier may be provided between the antenna 2 and the band pass filter 34 to amplify the power of the high frequency signal SHt. In addition, an antenna duplexer, a circulator, or the like may be provided between the antenna 2 and the mixers 5 and 33 in order to separate signals for transmission and reception.
　かくして、このように構成された第２の実施の形態においても、前述した第１の実施の形態とほぼ同様の作用効果を得ることができる。ローカル発振器３と周波数逓倍器４との間には、ローカル信号ＳL以外のノイズ信号Ｎを除去するフィルタ８を設けた。このため、周波数逓倍器４の相互変調歪みを抑制することができる。この結果、ミキサ３３には周波数逓倍器４からノイズスペクトラムが低減された信号が入力されるから、ミキサ３３から出力されるノイズを抑制することができ、通信信号帯域とノイズ帯域との重複を防ぐことができる。 Thus, also in the second embodiment configured as described above, substantially the same effects as those of the first embodiment described above can be obtained. A filter 8 is provided between the local oscillator 3 and the frequency multiplier 4 to remove noise signals N other than the local signal SL. Therefore, the intermodulation distortion of the frequency multiplier 4 can be suppressed. As a result, since the signal from which the noise spectrum is reduced from the frequency multiplier 4 is input to the mixer 33, the noise output from the mixer 33 can be suppressed, and the overlapping of the communication signal band and the noise band can be prevented. be able to.
　なお、前記第１の実施の形態では、無線通信装置として受信装置１を例示すると共に、前記第２の実施の形態では、無線通信装置として送受信装置３１を例示した。本発明はこれに限らず、無線通信装置は、送信機能だけを有する送信装置であってもよい。 In the first embodiment, the receiving device 1 is illustrated as a wireless communication device, and in the second embodiment, the transmitting and receiving device 31 is illustrated as a wireless communication device. The present invention is not limited to this, and the wireless communication apparatus may be a transmitting apparatus having only a transmitting function.
　前記各実施の形態では、ミリ波に用いる無線通信装置を例に挙げて説明したが、例えばマイクロ波のような他の周波数帯域の高周波信号に用いる無線通信装置に適用してもよい。 In each of the above embodiments, the wireless communication apparatus used for millimeter waves has been described as an example, but the present invention may be applied to a wireless communication apparatus used for high frequency signals of other frequency bands such as microwaves.
　また、前記各実施の形態で記載した周波数等の具体的な数値は、一例を示したものであり、例示した値に限らない。これらの数値は、例えば適用対象の仕様に応じて適宜設定される。 Further, specific numerical values such as the frequency described in each of the above-described embodiments are merely examples and are not limited to the exemplified values. These numerical values are appropriately set, for example, according to the specification of the application target.
　前記各実施の形態は例示であり、異なる実施の形態で示した構成の部分的な置換または組み合わせが可能であることは言うまでもない。 It is needless to say that each of the above embodiments is an exemplification, and partial replacement or combination of the configurations shown in the different embodiments is possible.
　次に、上記の実施の形態に含まれる発明について記載する。本発明は、所定の帯域幅をもった高周波信号を送信または受信するアンテナと、前記高周波信号よりも低い中心周波数のローカル信号を出力するローカル発振器と、前記ローカル信号を周波数逓倍し、前記ローカル発振器に電気的に接続された周波数逓倍器と、前記アンテナと前記周波数逓倍器とに接続されたミキサと、を備えた無線通信装置であって、前記ローカル発振器と前記周波数逓倍器との間には、前記ローカル信号を通過させ前記ローカル信号とは異なる周波数のノイズ信号を除去するフィルタが設けられ、前記フィルタは、前記ローカル信号の中心周波数と前記ノイズ信号の中心周波数との周波数差の絶対値が前記高周波信号の帯域幅よりも小さくなる関係を満たす前記ノイズ信号を除去することを特徴としている。これにより、周波数逓倍器の相互変調歪みを抑制して、ノイズの発生を防ぐことができる。 Next, the inventions included in the above embodiment will be described. The present invention comprises an antenna for transmitting or receiving a high frequency signal having a predetermined bandwidth, a local oscillator for outputting a local signal having a lower center frequency than the high frequency signal, and frequency-multiplying the local signal, the local oscillator A wireless communication device comprising: a frequency multiplier electrically connected to each other; and a mixer connected to the antenna and the frequency multiplier, the wireless communication device comprising: And a filter for passing the local signal and removing a noise signal having a frequency different from that of the local signal, wherein the filter has an absolute value of a frequency difference between a center frequency of the local signal and a center frequency of the noise signal. It is characterized in that the noise signal satisfying the relation smaller than the bandwidth of the high frequency signal is removed. Thereby, the intermodulation distortion of the frequency multiplier can be suppressed, and the generation of noise can be prevented.
　本発明では、前記フィルタは、前記ローカル信号を通過させて前記ノイズ信号を除去する帯域通過フィルタまたは帯域除去フィルタによって構成されている。フィルタが帯域通過フィルタであるときには、帯域通過フィルタによって、ローカル信号を通過させて、ローカル信号とは異なる周波数のノイズ信号を除去することができる。また、フィルタが帯域除去フィルタであるときには、帯域除去フィルタによって、ローカル信号を通過させてノイズ信号を除去することができる。 In the present invention, the filter is configured by a band pass filter or a band removal filter that passes the local signal and removes the noise signal. When the filter is a band pass filter, the band pass filter allows the local signal to pass and removes noise signals of a frequency different from the local signal. In addition, when the filter is a band elimination filter, the band elimination filter can pass the local signal and remove the noise signal.
　本発明では、前記フィルタは、インダクタ素子とキャパシタ素子とを組み合わせて構成されている。このため、受動素子を用いて簡易にフィルタを構成することができる。 In the present invention, the filter is configured by combining an inductor element and a capacitor element. Therefore, the filter can be easily configured using passive elements.
　本発明では、前記帯域通過フィルタはインダクタ素子とキャパシタ素子との直列共振回路を含んで構成されている。このため、直列共振回路の共振周波数をローカル信号の中心周波数に合わせることによって、帯域通過フィルタは、ローカル信号を通過させてノイズ信号を除去することができる。また、前記帯域除去フィルタはインダクタ素子とキャパシタ素子との並列共振回路を含んで構成されている。このため、並列共振回路の共振周波数をノイズ信号の中心周波数に合わせることによって、帯域除去フィルタは、ローカル信号を通過させてノイズ信号を除去することができる。 In the present invention, the band pass filter includes a series resonance circuit of an inductor element and a capacitor element. Therefore, by setting the resonant frequency of the series resonant circuit to the center frequency of the local signal, the band pass filter can pass the local signal and remove the noise signal. The band elimination filter is configured to include a parallel resonance circuit of an inductor element and a capacitor element. Therefore, by setting the resonant frequency of the parallel resonant circuit to the center frequency of the noise signal, the band elimination filter can pass the local signal and remove the noise signal.
　本発明では、前記ノイズ信号は、前記高周波信号とは異なる周波数帯の無線通信に使用される他の高周波信号である。このため、他の高周波信号がローカル信号に近い中心周波数を有するときでも、他の高周波信号によるノイズを抑制することができる。 In the present invention, the noise signal is another high frequency signal used for wireless communication of a frequency band different from that of the high frequency signal. Therefore, even when another high frequency signal has a center frequency close to that of the local signal, noise due to the other high frequency signal can be suppressed.
　１　受信装置（無線通信装置）
　２　アンテナ
　３　ローカル発振器
　４　周波数逓倍器
　５，３３　ミキサ
　８，２１，２２，２３　フィルタ
　８Ａ，２１Ａ，２１Ｂ　並列共振回路
　２２Ａ，２３Ａ，２３Ｂ　直列共振回路
　３１　送受信装置（無線通信装置） 1 Receiver (wireless communication device)
Reference Signs List 2 antenna 3 local oscillator 4 frequency multiplier 5, 33 mixers 8, 21, 22, 23 filters 8A, 21A, 21B parallel resonant circuits 22A, 23A, 23B series resonant circuits 31 transmitting / receiving apparatus (wireless communication apparatus)

Claims (5)

  1. 　所定の帯域幅をもった高周波信号を送信または受信するアンテナと、
    　前記高周波信号よりも低い中心周波数のローカル信号を出力するローカル発振器と、
    　前記ローカル信号を周波数逓倍し、前記ローカル発振器に電気的に接続された周波数逓倍器と、
    　前記アンテナと前記周波数逓倍器とに接続されたミキサと、を備えた無線通信装置であって、
    　前記ローカル発振器と前記周波数逓倍器との間には、前記ローカル信号を通過させ前記ローカル信号とは異なる周波数のノイズ信号を除去するフィルタが設けられ、
    　前記フィルタは、前記ローカル信号の中心周波数と前記ノイズ信号の中心周波数との周波数差の絶対値が前記高周波信号の帯域幅よりも小さくなる関係を満たす前記ノイズ信号を除去することを特徴とする無線通信装置。     An antenna for transmitting or receiving a high frequency signal having a predetermined bandwidth;
    A local oscillator that outputs a local signal of a center frequency lower than the high frequency signal;
    A frequency multiplier that frequency-multiplies the local signal and is electrically connected to the local oscillator;
    A radio communication apparatus comprising: a mixer connected to the antenna and the frequency multiplier;
    A filter is provided between the local oscillator and the frequency multiplier for passing the local signal and removing a noise signal of a frequency different from that of the local signal.
    The filter is configured to remove the noise signal satisfying a relationship in which an absolute value of a frequency difference between a center frequency of the local signal and a center frequency of the noise signal is smaller than a bandwidth of the high frequency signal. Communication device.
  2. 　前記フィルタは、前記ローカル信号を通過させて前記ノイズ信号を除去する帯域通過フィルタまたは帯域除去フィルタによって構成されていることを特徴とする請求項１に記載の無線通信装置。 The wireless communication apparatus according to claim 1, wherein the filter is configured by a band pass filter or a band elimination filter that passes the local signal and removes the noise signal.
  3. 　前記フィルタは、インダクタ素子とキャパシタ素子とを組み合わせて構成されていることを特徴とする請求項１または２に記載の無線通信装置。 The wireless communication device according to claim 1, wherein the filter is configured by combining an inductor element and a capacitor element.
  4. 　前記帯域通過フィルタは、インダクタ素子とキャパシタ素子との直列共振回路を含んで構成され、前記帯域除去フィルタは、インダクタ素子とキャパシタ素子との並列共振回路を含んで構成されていることを特徴とする請求項２に記載の無線通信装置。 The band pass filter is configured to include a series resonant circuit of an inductor element and a capacitor element, and the band elimination filter is configured to include a parallel resonant circuit of an inductor element and a capacitor element. The wireless communication device according to claim 2.
  5. 　前記ノイズ信号は、前記高周波信号とは異なる周波数帯の無線通信に使用される他の高周波信号であることを特徴とする請求項１ないし４のいずれかに記載の無線通信装置。 The wireless communication device according to any one of claims 1 to 4, wherein the noise signal is another high frequency signal used for wireless communication of a frequency band different from that of the high frequency signal.
PCT/JP2018/041483 2017-11-30 2018-11-08 Wireless communication apparatus WO2019107105A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2019557107A JP6737409B2 (en) 2017-11-30 2018-11-08 Wireless communication device
KR1020207015056A KR102348617B1 (en) 2017-11-30 2018-11-08 radio communication device
CN201880077421.0A CN111492588B (en) 2017-11-30 2018-11-08 Wireless communication device
US16/886,422 US11050448B2 (en) 2017-11-30 2020-05-28 Wireless communication device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2017230383 2017-11-30
JP2017-230383 2017-11-30

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US16/886,422 Continuation US11050448B2 (en) 2017-11-30 2020-05-28 Wireless communication device

Publications (1)

Publication Number Publication Date
WO2019107105A1 true WO2019107105A1 (en) 2019-06-06

Family

ID=66665542

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2018/041483 WO2019107105A1 (en) 2017-11-30 2018-11-08 Wireless communication apparatus

Country Status (5)

Country Link
US (1) US11050448B2 (en)
JP (1) JP6737409B2 (en)
KR (1) KR102348617B1 (en)
CN (1) CN111492588B (en)
WO (1) WO2019107105A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024100704A1 (en) * 2022-11-07 2024-05-16 日本電信電話株式会社 Wireless communication transceiver

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04302553A (en) * 1991-03-29 1992-10-26 Mitsui Mining & Smelting Co Ltd Transmitter and receiver for spread spectrum communication and spread spectrum communication equipment
JPH10163918A (en) * 1996-12-02 1998-06-19 Sharp Corp Radio communication equipment
JP2003179513A (en) * 2001-10-02 2003-06-27 Matsushita Electric Ind Co Ltd Demodulator
JP2012222817A (en) * 2011-04-07 2012-11-12 Commissariat A L'energie Atomique Et Aux Energies Alternatives Radio frequency transmission or reception chain with automatic impedance matching function and automatic impedance matching method
JP2014195168A (en) * 2013-03-28 2014-10-09 Japan Radio Co Ltd Receiver and noise correction method

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0629774A (en) * 1992-07-07 1994-02-04 Tdk Corp Piezoelectric ceramic filter circuit and piezoelectric ceramic filter
US6614837B1 (en) * 1998-09-25 2003-09-02 Skyworks Solutions, Inc. Device system and method for low noise radio frequency transmission
DE60233242D1 (en) * 2001-08-29 2009-09-17 Sanyo Electric Co SIGNAL GENERATION DEVICE
JP2004129076A (en) * 2002-10-04 2004-04-22 Sharp Corp Frequency converting circuit, tuner using it, and set top box for catv reception
US7209716B2 (en) * 2003-02-27 2007-04-24 Ntt Docomo, Inc. Radio communication system, radio station, and radio communication method
JP4100199B2 (en) 2003-03-11 2008-06-11 住友電気工業株式会社 Digital broadcast wave relay method, transmitter and receiver
JP3686074B1 (en) * 2004-02-23 2005-08-24 シャープ株式会社 Wireless receiving circuit and wireless portable device
JP2009010604A (en) 2007-06-27 2009-01-15 Sharp Corp Receiver
KR20100069485A (en) * 2008-12-16 2010-06-24 한국전자통신연구원 Milimeterwave transceriver using single frequency synthesizer
DE112010005279B4 (en) * 2010-02-17 2017-03-30 Murata Manufacturing Co., Ltd. Device for elastic waves
US20140141738A1 (en) * 2012-11-19 2014-05-22 Rf Micro Devices, Inc. Self-tuning amplification device
CN106464372B (en) * 2014-05-14 2019-05-24 华为技术有限公司 Transmitter, receiver and frequency deviation correcting method
GB2547099B (en) * 2014-07-25 2021-02-17 Allen Vanguard Corp System and method for ultra wideband radio frequency scanning and signal generation
US9912425B2 (en) * 2014-12-15 2018-03-06 Intel Corporation Radio frequency transceiver with local oscillator control for multi-carrier applications
US10079616B2 (en) * 2014-12-19 2018-09-18 University Of Washington Devices and methods for backscatter communication using one or more wireless communication protocols including bluetooth low energy examples
US9590644B2 (en) * 2015-02-06 2017-03-07 Silicon Laboratories Inc. Managing spurs in a radio frequency circuit
JP6730611B2 (en) * 2017-01-11 2020-07-29 富士通株式会社 Wireless analysis device, wireless analysis method, and program
JP6798642B2 (en) * 2018-04-26 2020-12-09 株式会社村田製作所 Wireless communication module

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04302553A (en) * 1991-03-29 1992-10-26 Mitsui Mining & Smelting Co Ltd Transmitter and receiver for spread spectrum communication and spread spectrum communication equipment
JPH10163918A (en) * 1996-12-02 1998-06-19 Sharp Corp Radio communication equipment
JP2003179513A (en) * 2001-10-02 2003-06-27 Matsushita Electric Ind Co Ltd Demodulator
JP2012222817A (en) * 2011-04-07 2012-11-12 Commissariat A L'energie Atomique Et Aux Energies Alternatives Radio frequency transmission or reception chain with automatic impedance matching function and automatic impedance matching method
JP2014195168A (en) * 2013-03-28 2014-10-09 Japan Radio Co Ltd Receiver and noise correction method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024100704A1 (en) * 2022-11-07 2024-05-16 日本電信電話株式会社 Wireless communication transceiver

Also Published As

Publication number Publication date
JPWO2019107105A1 (en) 2020-05-28
KR102348617B1 (en) 2022-01-06
CN111492588A (en) 2020-08-04
KR20200080277A (en) 2020-07-06
CN111492588B (en) 2022-03-25
JP6737409B2 (en) 2020-08-05
US20200295792A1 (en) 2020-09-17
US11050448B2 (en) 2021-06-29

Similar Documents

Publication Publication Date Title
US8295333B2 (en) Method and system for inter-PCB communication utilizing a spatial multi-link repeater
US9094104B2 (en) Transceiver front-end
CN108847866B (en) Radio frequency front end adjacent channel interference suppression circuit and WLAN access equipment
WO2003069792A1 (en) Radio communication method and system for performing communication among a plurality of radio communication terminals
US8060020B2 (en) Apparatus and method for removing interference signal using selective frequency phase converter
JP4910586B2 (en) Transmission / reception device and electronic apparatus using the same
KR100714699B1 (en) Wireless transceiver supporting plurality of communication/broadcast service
EP2371058B1 (en) Radio receiver
KR100404772B1 (en) Direct conversion receiver and transceiver
WO2019107105A1 (en) Wireless communication apparatus
JP2017508325A (en) Local oscillator signal generation
US8731122B1 (en) Spurious component reduction
WO2021184371A1 (en) Receiving apparatus, transmitting apparatus, and signal processing method
US20090264083A1 (en) Wireless communication system
JP2008533792A (en) Electronic device for generating a local oscillator signal with a fundamental frequency of partial equivalent frequency
JP2012049790A (en) Transmitter and receiver
JP2010193160A (en) Radio receiver and method of receiving radio signal
KR101262343B1 (en) Radio frequency transmitter-receiver
EP3560105A1 (en) Fully integrated radio frequency terminal system
US20030201837A1 (en) Modulating module incorporating a harmonically distorted modulator, and frequency shifting module with a harmonic mixer
JP2007028303A (en) Frequency converting apparatus
JPH09191264A (en) Transmitter-receiver, receiver, communication system and reception section evaluation device
US8954018B2 (en) Tunable wideband distribution circuit
JP2019220793A (en) Frequency converter
JP2006229404A (en) Double frequency converter

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18884785

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2019557107

Country of ref document: JP

ENP Entry into the national phase

Ref document number: 20207015056

Country of ref document: KR

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18884785

Country of ref document: EP

Kind code of ref document: A1